fix(#75): preserve Race Hub meeting/session on Weekend return

Add an explicit Back to Weekend link that deep-links to /?meeting_key&session_key,
restore that focus on the adaptive Weekend home with a Continue analysis CTA, and
regenerate Race Hub visual baselines against the integrated #80 nav.

Co-authored-by: Cursor <cursoragent@cursor.com>

.agents/harnesses.sh

@@ -25,7 +25,8 @@ EOF
 
 harness_claude() {                      # Claude Code — print mode, auto-accept edits
   local dir="$1" prompt="$2"
-  ( cd "$dir" && claude -p "$(cat "$prompt")" --permission-mode acceptEdits )
+  local model="${BOXBOX_CLAUDE_MODEL:-opus}"
+  ( cd "$dir" && claude -p "$(cat "$prompt")" --model "$model" --effort high --permission-mode acceptEdits )
 }
 
 harness_codex() {                       # OpenAI Codex CLI — non-interactive exec, full auto
@@ -40,7 +41,8 @@ harness_opencode() {                    # opencode — non-interactive run
 
 harness_cursor() {                      # Cursor CLI agent — composer-2.5, headless full-auto
   local dir="$1" prompt="$2"
-  ( cd "$dir" && cursor-agent -p "$(cat "$prompt")" --model composer-2.5 --force --trust )
+  local model="${BOXBOX_CURSOR_MODEL:-composer-2.5}"
+  ( cd "$dir" && cursor-agent -p "$(cat "$prompt")" --model "$model" --force --trust )
 }
 
 harness_agy() {                         # Antigravity CLI — disabled until headless is verified

.agents/skills/groom/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: groom
-description: Groom a box-box GitHub issue into a Ready spec via a seeded grill-me interrogation. Use when the user asks to groom an issue, for example "/groom <issue-number>" or "$groom <issue-number>" with optional "--lens architect". Single-issue path: asks targeted questions, writes a structured spec into the issue body, sets Effort/Priority, and leaves Stage at Research for approval.
+description: 'Groom a box-box GitHub issue into a Ready spec via a seeded grill-me interrogation. Use when the user asks to groom an issue, for example "/groom <issue-number>" or "$groom <issue-number>" with optional "--lens architect". Single-issue path: asks targeted questions, writes a structured spec into the issue body, sets Effort/Priority, and leaves Stage at Research for approval.'
 argument-hint: <issue-number> [--lens architect]
 ---
 

.agents/skills/implement/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: implement
-description: Dispatch a Ready box-box issue to a coding harness (claude/codex/opencode/pi/cursor) in an isolated git worktree, run the build gate, and open a PR. Use when supervising implementation via "/implement <issue-number> --harness <name> [--dry-run]" or from any harness terminal with .agents/bin/dev.
+description: 'Dispatch a Ready box-box issue to a coding harness (claude/codex/opencode/pi/cursor) in an isolated git worktree, run the build gate, and open a PR. Use when supervising implementation via "/implement <issue-number> --harness <name> [--dry-run]" or from any harness terminal with .agents/bin/dev.'
 argument-hint: <issue-number> --harness <claude|codex|opencode|pi|cursor> [--dry-run]
 ---
 

.agents/skills/lens-architect/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: lens-architect
-description: Grill/analyze a box-box issue or epic from a software-architecture perspective and post the findings as a comment. Use standalone as "/lens-architect <issue-number>" for an on-the-fly architecture review, or let /groom compose it via "--lens architect". Reads the base grill + architect persona and focuses on reuse, data flow, seams, testability, and risk.
+description: 'Grill/analyze a box-box issue or epic from a software-architecture perspective and post the findings as a comment. Use standalone as "/lens-architect <issue-number>" for an on-the-fly architecture review, or let /groom compose it via "--lens architect". Reads the base grill + architect persona and focuses on reuse, data flow, seams, testability, and risk.'
 argument-hint: <issue-number>
 ---
 

.agents/skills/review/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: review
-description: Locally review a box-box PR against its linked GitHub issue spec, run tests, capture visual screenshots when applicable, create a .review packet, and post a GitHub PR comment. Use when a ticket implementation is ready for independent local review before the human merge gate.
+description: 'Locally review a box-box PR against its linked GitHub issue spec, run tests, capture visual screenshots when applicable, create a .review packet, and post a GitHub PR comment. Use when a ticket implementation is ready for independent local review before the human merge gate.'
 argument-hint: <pr-number> [--harness <name>] [--publish-screenshots]
 ---
 

.agents/skills/write-spec/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: write-spec
-description: Render a groomed design into the box-box Ready-spec template and write it into a GitHub issue body, then set Effort and Priority. Called by /groom after a grill session, or run standalone as "/write-spec <issue-number>" to (re)write an issue's spec from agreed decisions. Does not change Stage.
+description: 'Render a groomed design into the box-box Ready-spec template and write it into a GitHub issue body, then set Effort and Priority. Called by /groom after a grill session, or run standalone as "/write-spec <issue-number>" to (re)write an issue''s spec from agreed decisions. Does not change Stage.'
 argument-hint: <issue-number>
 ---
 

docs/product/v0.4.0/README.md

@@ -0,0 +1,32 @@
+# v0.4.0 — Current Weekend & Product Truth
+
+Product research references for the v0.4.0 feature sprint.
+
+## Direction
+
+The sprint replaces route-first navigation with a state-aware Weekend experience:
+
+- Weekend is the adaptive home for what happened, what is live, and what is next.
+- Preview content folds into Weekend before a session.
+- Live remains a stable deep link and becomes Weekend's active-session state.
+- Race Hub remains explicit completed-session analysis rather than a primary landing destination.
+- Championship and Briefing remain dedicated destinations.
+- Explore owns secondary discovery; Admin moves to operator utility.
+
+## Mockups
+
+- `mockups/weekend-between-races.png` — desktop between-races/post-weekend state.
+- `mockups/weekend-live.png` — desktop active-session state; the circuit is static sector context, not live GPS.
+- `mockups/weekend-between-sessions-mobile.png` — 390×844 between-session state.
+
+These are directional references, not pixel-perfect specifications. Implementations must preserve the established box-box visual language, accessibility, data constraints, and responsive behavior while satisfying their issue acceptance criteria.
+
+## Constraints
+
+- No OpenF1 REST dependency during active sessions.
+- Public live GPS is not assumed to be available.
+- Championship round numbers exclude tests and cancelled meetings.
+- Connection health, live-session state, archive availability, and local-analysis readiness are separate concepts.
+- Future sessions must not render empty post-session analysis.
+
+The authoritative product decisions and research packet are recorded in GitHub issue #71 under epic #70.

frontend/src/api.ts

@@ -2,15 +2,20 @@ import type {
   ArticleContent,
   CarDataSample,
   ChampionshipHub,
+  DriverSummary,
+  EnrichedGrid,
+  EnrichedResult,
   LapsComparisonResponse,
   LiveStateResponse,
   LiveSessionMeta,
   Meeting,
   NewsItem,
   RaceHub,
+  ReplayFramesResponse,
   Session,
   TrackOutline,
   Weekend,
+  WeekendContext,
 } from './types'
 
 export async function fetchRaceHub(sessionKey: number): Promise<RaceHub> {
@@ -40,7 +45,11 @@ export async function fetchLocalMeetings(year: number): Promise<Meeting[]> {
 }
 
 export async function fetchSeasonMeetings(year: number): Promise<Meeting[]> {
-  const res = await fetch(`/api/v1/meetings?year=${year}&source=openf1`)
+  return fetchMeetings(year, 'openf1')
+}
+
+export async function fetchMeetings(year: number, source = 'auto'): Promise<Meeting[]> {
+  const res = await fetch(`/api/v1/meetings?year=${year}&source=${source}`)
   if (!res.ok) {
     throw new Error(`API ${res.status}: ${res.statusText}`)
   }
@@ -48,6 +57,47 @@ export async function fetchSeasonMeetings(year: number): Promise<Meeting[]> {
   return Array.isArray(meetings) ? meetings : []
 }
 
+export async function fetchResults(sessionKey: number, source = 'auto'): Promise<EnrichedResult[]> {
+  const res = await fetch(`/api/v1/results?session_key=${sessionKey}&source=${source}`)
+  if (!res.ok) {
+    throw new Error(`API ${res.status}: ${res.statusText}`)
+  }
+  const results = await res.json()
+  return Array.isArray(results) ? results : []
+}
+
+export async function fetchStartingGrid(sessionKey: number, source = 'auto'): Promise<EnrichedGrid[]> {
+  const res = await fetch(`/api/v1/grid?session_key=${sessionKey}&source=${source}`)
+  if (!res.ok) {
+    throw new Error(`API ${res.status}: ${res.statusText}`)
+  }
+  const grid = await res.json()
+  return Array.isArray(grid) ? grid : []
+}
+
+export async function fetchTrackOutline(circuitKey: number, year: number): Promise<TrackOutline | null> {
+  const res = await fetch(`/api/v1/track-outline?circuit_key=${circuitKey}&year=${year}`)
+  if (!res.ok) return null
+  const data = await res.json()
+  if (data?.error || !Array.isArray(data?.points) || data.points.length < 2) return null
+  return data as TrackOutline
+}
+
+export async function fetchReplayFrames(
+  sessionKey: number,
+  intervalMs = 5000,
+): Promise<ReplayFramesResponse> {
+  const params = new URLSearchParams({
+    session_key: String(sessionKey),
+    interval_ms: String(intervalMs),
+  })
+  const res = await fetch(`/api/v1/replay/frames?${params}`)
+  if (!res.ok) {
+    throw new Error(`API ${res.status}: ${res.statusText}`)
+  }
+  return res.json()
+}
+
 export async function fetchSessions(meetingKey: number, source = 'openf1'): Promise<Session[]> {
   const res = await fetch(`/api/v1/sessions?meeting_key=${meetingKey}&source=${source}`)
   if (!res.ok) {
@@ -65,6 +115,20 @@ export async function fetchWeekend(meetingKey: number): Promise<Weekend> {
   return res.json()
 }
 
+// fetchWeekendContext consumes the canonical /api/v1/weekend-context endpoint
+// (backend story #72). The response is the authoritative WeekendContext shape and
+// is used verbatim as the Weekend home's source of truth. Any HTTP error throws
+// so the hook can surface an explicit error state; there is no client-side
+// re-derivation of the contract. Race Hub bare-default landing also reads this
+// for `default_analysis_session` (#75).
+export async function fetchWeekendContext(): Promise<WeekendContext> {
+  const res = await fetch('/api/v1/weekend-context')
+  if (!res.ok) {
+    throw new Error(`API ${res.status}: ${res.statusText}`)
+  }
+  return res.json()
+}
+
 export async function fetchChampionshipHub(year?: number): Promise<ChampionshipHub> {
   const params = new URLSearchParams({ source: 'auto' })
   if (year) params.set('year', year.toString())
@@ -76,6 +140,19 @@ export async function fetchChampionshipHub(year?: number): Promise<ChampionshipH
   return res.json()
 }
 
+export async function fetchDriverSummary(
+  driverNumber: number,
+  year?: number,
+): Promise<DriverSummary> {
+  const params = new URLSearchParams({ driver_number: String(driverNumber) })
+  if (year) params.set('year', String(year))
+  const res = await fetch(`/api/v1/driver/summary?${params.toString()}`)
+  if (!res.ok) {
+    throw new Error(`API ${res.status}: ${res.statusText}`)
+  }
+  return res.json()
+}
+
 export async function fetchLiveState(): Promise<LiveStateResponse> {
   const res = await fetch('/api/v1/live/state')
   if (!res.ok) {

frontend/src/components/ChapterStrip.tsx

@@ -0,0 +1,116 @@
+import { useEffect, useRef } from 'react'
+import { BookOpen } from 'lucide-react'
+import type { Chapter } from '../types'
+import {
+  activeChapterIndex,
+  chapterKindLabel,
+  chapterLapRange,
+  chapterStartScrub,
+} from '../lib/chapters'
+import { EmptyStateCard } from './EmptyStateCard'
+import '../styles/chapters.css'
+
+interface Props {
+  chapters: Chapter[]
+  scrubTime: number | null
+  tMin: number
+  tRange: number
+  tourActive: boolean
+  tourChapterIndex: number | null
+  /** Explicit selection from a chapter click; wins over scrub-derived active. */
+  selectedChapterIndex?: number | null
+  onChapterClick: (index: number, scrub: number) => void
+  onTourToggle: () => void
+}
+
+export function ChapterStrip({
+  chapters,
+  scrubTime,
+  tMin,
+  tRange,
+  tourActive,
+  tourChapterIndex,
+  selectedChapterIndex = null,
+  onChapterClick,
+  onTourToggle,
+}: Props) {
+  const scrollRef = useRef<HTMLDivElement>(null)
+  const activeIndex = activeChapterIndex(chapters, scrubTime, tMin, tRange)
+  const highlightedIndex = tourActive
+    ? tourChapterIndex
+    : (selectedChapterIndex ?? activeIndex)
+
+  useEffect(() => {
+    if (highlightedIndex === null || !scrollRef.current) return
+    const card = scrollRef.current.querySelector<HTMLElement>(
+      `[data-testid="chapter-card-${highlightedIndex}"]`,
+    )
+    card?.scrollIntoView?.({ behavior: 'smooth', inline: 'center', block: 'nearest' })
+  }, [highlightedIndex])
+
+  if (chapters.length === 0) {
+    return (
+      <div className="chapter-strip" data-testid="chapter-strip">
+        <EmptyStateCard
+          icon={BookOpen}
+          title="No story chapters"
+          hint="This session does not have enough race-control or position data to build narrative chapters."
+          testId="chapter-strip-empty"
+          className="chapter-strip-empty-card"
+        />
+      </div>
+    )
+  }
+
+  return (
+    <div className="chapter-strip" data-testid="chapter-strip">
+      <div className="chapter-strip-header">
+        <span className="chapter-strip-title">Race chapters</span>
+        <div className="chapter-strip-actions">
+          <button
+            type="button"
+            className={`chapter-tour-btn ${tourActive ? 'active' : ''}`}
+            onClick={onTourToggle}
+            aria-pressed={tourActive}
+          >
+            {tourActive ? 'Exit 90s' : '90s tour'}
+          </button>
+        </div>
+      </div>
+      <div className="chapter-strip-scroll-wrap">
+        <div
+          ref={scrollRef}
+          className="chapter-strip-scroll"
+          role="list"
+          aria-label="Race story chapters"
+        >
+          {chapters.map((chapter, index) => {
+            const scrub = chapterStartScrub(chapter, tMin, tRange) ?? index / Math.max(chapters.length - 1, 1)
+            const isActive = highlightedIndex === index
+            const headline = chapter.headline || chapter.title
+
+            return (
+              <button
+                key={`${chapter.kind}-${chapter.start_lap}-${index}`}
+                type="button"
+                role="listitem"
+                className={`chapter-card ${isActive ? (tourActive ? 'tour-active' : 'active') : ''}`}
+                onClick={() => onChapterClick(index, scrub)}
+                aria-current={isActive ? 'true' : undefined}
+                data-testid={`chapter-card-${index}`}
+              >
+                <div className="chapter-card-top">
+                  <span className={`chapter-kind chapter-kind--${chapter.kind}`}>
+                    {chapterKindLabel(chapter.kind)}
+                  </span>
+                  <span className="chapter-lap-range">{chapterLapRange(chapter)}</span>
+                </div>
+                <span className="chapter-headline">{headline}</span>
+              </button>
+            )
+          })}
+        </div>
+      </div>
+    </div>
+  )
+}

frontend/src/components/EmptyStateCard.tsx

@@ -0,0 +1,20 @@
+import type { LucideIcon } from 'lucide-react'
+import type { ReactNode } from 'react'
+
+interface Props {
+  icon: LucideIcon
+  title: string
+  hint: ReactNode
+  testId?: string
+  className?: string
+}
+
+export function EmptyStateCard({ icon: Icon, title, hint, testId, className = '' }: Props) {
+  return (
+    <div className={`empty-state ui-card ${className}`.trim()} data-testid={testId}>
+      <Icon size={32} className="empty-state-icon" aria-hidden />
+      <div className="empty-state-title">{title}</div>
+      <div className="empty-state-desc">{hint}</div>
+    </div>
+  )
+}

frontend/src/components/Nav.tsx

@@ -1,33 +1,66 @@
 import { Link } from '@tanstack/react-router'
+import { Compass, FileText, Home, Trophy } from 'lucide-react'
 
+const PRIMARY = [
+  { to: '/', label: 'Weekend', icon: Home, exact: true },
+  { to: '/championship', label: 'Championship', icon: Trophy, exact: false },
+  { to: '/briefing', label: 'Briefing', icon: FileText, exact: false },
+  { to: '/explore', label: 'Explore', icon: Compass, exact: false },
+] as const
+
+/**
+ * Nav renders one primary navigation system per breakpoint:
+ *   - Desktop/tablet: the top bar's `aria-label="Primary"` links.
+ *   - Mobile (≤640px): the bottom `aria-label="Primary"` bar; the top bar's links
+ *     are hidden via CSS so the two are never both active at once.
+ *
+ * Admin is an operator utility, deliberately outside every Primary landmark — it
+ * lives in a plain toolbar slot and never appears in the mobile bottom nav.
+ */
 export function Nav() {
   return (
-    <nav className="app-nav">
+    <>
-      <Link to="/" className="nav-logo">
+      <header className="app-nav">
-        box<em>-</em>box
+        <Link to="/" className="nav-logo">
-      </Link>
+          box<em>-</em>box
-      <div className="nav-links">
-        <Link to="/" activeProps={{ className: 'active' }} activeOptions={{ exact: true }}>
-          Command
         </Link>
-        <Link to="/live" activeProps={{ className: 'active' }}>
+        <nav className="nav-links" aria-label="Primary">
-          Live
+          {PRIMARY.map(({ to, label, exact }) => (
-        </Link>
+            <Link
-        <Link to="/race-hub" search={{}} activeProps={{ className: 'active' }}>
+              key={to}
-          Race Hub
+              to={to}
-        </Link>
+              activeProps={{ className: 'active' }}
-        <Link to="/championship" activeProps={{ className: 'active' }}>
+              activeOptions={exact ? { exact: true } : undefined}
-          Championship
+            >
-        </Link>
+              {label}
-        <Link to="/briefing" activeProps={{ className: 'active' }}>
+            </Link>
-          Briefing
+          ))}
-        </Link>
+        </nav>
-      </div>
+        <div className="nav-utility" role="toolbar" aria-label="Operator utilities">
-      <div className="nav-utility">
+          <Link
-        <Link to="/admin" className="nav-utility-link" activeProps={{ className: 'nav-utility-link active' }}>
+            to="/admin"
-          Admin
+            className="nav-utility-link"
-        </Link>
+            activeProps={{ className: 'nav-utility-link active' }}
-      </div>
+          >
-    </nav>
+            Admin
+          </Link>
+        </div>
+      </header>
+
+      <nav className="app-bottom-nav" aria-label="Primary">
+        {PRIMARY.map(({ to, label, icon: Icon, exact }) => (
+          <Link
+            key={to}
+            to={to}
+            className="bottom-nav-link"
+            activeProps={{ className: 'bottom-nav-link active' }}
+            activeOptions={exact ? { exact: true } : undefined}
+          >
+            <Icon size={18} aria-hidden="true" />
+            <span>{label}</span>
+          </Link>
+        ))}
+      </nav>
+    </>
   )
 }

frontend/src/components/OverviewView.tsx

@@ -1,6 +1,5 @@
 import type { RaceHub } from '../types'
 import { compareFinishPosition, formatDuration, formatGap, formatLapTime } from '../utils'
-import { countRaceHubDatasets } from '../lib/coverage'
 import { Thermometer, Map, Droplets, Wind, CloudRain } from 'lucide-react'
 
 interface Props {
@@ -17,7 +16,6 @@ export function OverviewView({ data }: Props) {
   const fastest = pickFastestLap(data)
   const latestWeather = data.weather.length > 0 ? data.weather[data.weather.length - 1] : null
   const rcHighlights = data.race_control.slice(-3).reverse()
-  const coverage = countRaceHubDatasets(data.datasets)
 
   const sessionType = (data.session?.session_type ?? '').toLowerCase()
   const isRace = sessionType.includes('race')
@@ -129,28 +127,6 @@ export function OverviewView({ data }: Props) {
             </ul>
           )}
         </section>
-
-        <section className="rh-panel ui-card">
-          <div className="sec-header">
-            <span className="sec-title">Local Coverage</span>
-            <span className="sec-meta mono">
-              {coverage.available}/{coverage.total}
-            </span>
-          </div>
-          <div className="rh-coverage-meter" aria-hidden="true">
-            <div
-              className="rh-coverage-fill"
-              style={{ width: `${(coverage.available / coverage.total) * 100}%` }}
-            />
-          </div>
-          <div className="rh-empty-line" style={{ marginTop: 'var(--s2)' }}>
-            {coverage.available === coverage.total
-              ? 'Every Race Hub dataset is local for this session.'
-              : `${coverage.total - coverage.available} dataset${
-                  coverage.total - coverage.available === 1 ? '' : 's'
-                } not ingested yet — see Data Status tab.`}
-          </div>
-        </section>
       </div>
     </div>
   )

frontend/src/components/PaddockBriefing.tsx

@@ -1,7 +1,23 @@
+import { useMemo } from 'react'
 import { useQuery } from '@tanstack/react-query'
 import { Link } from '@tanstack/react-router'
-import { fetchNews } from '../api'
+import {
+  fetchChampionshipHub,
+  fetchNews,
+  fetchSeasonMeetings,
+  fetchSeasons,
+} from '../api'
+import {
+  activeDigestWindow,
+  gpWindows,
+  itemsForWindow,
+  sinceLastLabel,
+  tagColour,
+  tagItems,
+  topTags,
+} from '../lib/digest'
 import { timeAgo } from '../utils'
+import '../styles/digest.css'
 
 const SOURCE_DISPLAY: Record<string, string> = {
   'fia': 'FIA',
@@ -14,14 +30,53 @@ const SOURCE_DISPLAY: Record<string, string> = {
 }
 
 export function PaddockBriefing() {
+  const now = useMemo(() => new Date(), [])
+
   const { data: news, isLoading, isError } = useQuery({
     queryKey: ['news'],
     queryFn: () => fetchNews(100),
     staleTime: 60_000,
   })
 
+  const seasonsQuery = useQuery({
+    queryKey: ['seasons'],
+    queryFn: fetchSeasons,
+  })
+  const latestSeason = seasonsQuery.data?.[0] ?? null
+
+  const meetingsQuery = useQuery({
+    queryKey: ['season-meetings', latestSeason],
+    queryFn: () => fetchSeasonMeetings(latestSeason!),
+    enabled: latestSeason != null,
+  })
+
+  const hubQuery = useQuery({
+    queryKey: ['championship-hub', latestSeason],
+    queryFn: () => fetchChampionshipHub(latestSeason!),
+    enabled: latestSeason != null,
+  })
+
+  const meetings = meetingsQuery.data ?? []
+  const hub = hubQuery.data
+  const tagged = useMemo(
+    () => tagItems(news ?? [], hub?.drivers ?? [], hub?.teams ?? []),
+    [news, hub],
+  )
+
+  const windows = useMemo(() => gpWindows(meetings, now), [meetings, now])
+  const activeWindow = useMemo(
+    () => activeDigestWindow(windows, meetings, now),
+    [windows, meetings, now],
+  )
+  const sinceItems = useMemo(
+    () => itemsForWindow(tagged, activeWindow),
+    [tagged, activeWindow],
+  )
+  const sinceTags = useMemo(() => topTags(sinceItems, 4), [sinceItems])
+  const sinceLabel = sinceLastLabel(meetings, now)
+
   const unreadCount = news?.filter((i) => !i.read_at).length ?? 0
-  const preview = news?.slice(0, 5) ?? []
+  const preview = sinceItems.length > 0 ? sinceItems.slice(0, 5) : (tagged.slice(0, 5))
 
   return (
     <section className="cc-briefing" data-testid="paddock-briefing">
@@ -37,6 +92,27 @@ export function PaddockBriefing() {
         </Link>
       </div>
 
+      {meetings.length > 0 && (
+        <div className="cc-brief-digest-meta" data-testid="cc-brief-digest-meta">
+          <span>Since {sinceLabel}</span>
+          <span>·</span>
+          <span>{sinceItems.length} items</span>
+          {sinceTags.length > 0 && (
+            <div className="cc-brief-digest-tags">
+              {sinceTags.map((tag) => (
+                <span
+                  key={tag.key}
+                  className="cc-brief-tag"
+                  style={{ borderColor: tagColour(tag.colour) }}
+                >
+                  {tag.label}
+                </span>
+              ))}
+            </div>
+          )}
+        </div>
+      )}
+
       {isLoading && <div className="briefing-state loading-state">loading…</div>}
       {isError && <div className="briefing-state error-box">Failed to load briefing</div>}
 

frontend/src/components/PreSessionView.tsx

@@ -0,0 +1,141 @@
+import type { Session } from '../types'
+import { RACE_HUB_DATASETS } from '../lib/coverage'
+import { formatCountdown, formatSessionScheduleTime, sessionStartTime } from '../lib/schedule'
+import {
+  sessionStateDescription,
+  type SessionState,
+} from '../lib/sessionState'
+
+const EXPECTED_LABELS: Record<string, string> = {
+  results: 'Final results',
+  starting_grid: 'Starting grid',
+  stints: 'Tyre strategy',
+  pit_stops: 'Pit stops',
+  positions: 'Position changes',
+  laps: 'Lap times',
+  race_control: 'Race control',
+  weather: 'Track conditions',
+}
+
+interface PreSessionProps {
+  session: Session
+  sessionName: string
+  now: Date
+}
+
+/**
+ * Purpose-built view for a session that has not run yet. Instead of rendering
+ * empty Winner / Podium / Pole / Strategy / Compare cards, it explains that the
+ * session is upcoming and previews the analysis that will appear once the data
+ * is ingested.
+ */
+export function PreSessionView({ session, sessionName, now }: PreSessionProps) {
+  const start = sessionStartTime(session)
+  const expected = RACE_HUB_DATASETS.filter((key) => EXPECTED_LABELS[key])
+
+  return (
+    <div className="rh-presession" data-testid="rh-presession">
+      <section className="rh-presession-band">
+        <span className="rh-presession-eyebrow mono">Upcoming session</span>
+        <h2 className="rh-presession-title">{sessionName}</h2>
+        <p className="rh-presession-sub">
+          This session hasn’t run yet, so there’s no result to analyse. Winner,
+          podium, pole, strategy and comparison views will appear here once the
+          session completes and its data is ingested.
+        </p>
+        <div className="rh-presession-countdown mono" data-testid="rh-presession-countdown">
+          {start
+            ? `Starts ${formatSessionScheduleTime(session.date_start)} · in ${formatCountdown(start, now)}`
+            : 'Start time to be confirmed.'}
+        </div>
+      </section>
+
+      <div className="data-section">
+        <div className="sec-header">
+          <span className="sec-title">Expected once complete</span>
+        </div>
+        <div className="rh-expected-grid">
+          {expected.map((key) => (
+            <div key={key} className="rh-expected-card">
+              <span className="rh-expected-dot" aria-hidden="true" />
+              <span>{EXPECTED_LABELS[key]}</span>
+            </div>
+          ))}
+        </div>
+      </div>
+    </div>
+  )
+}
+
+interface PhaseProps {
+  state: Extract<SessionState, 'preparing' | 'unavailable' | 'cancelled'>
+  sessionName: string
+  onOpenDiagnostics?: () => void
+}
+
+/**
+ * Distinct fan-facing surfaces for settling/preparing and unavailable sessions.
+ * Genuine request failures stay on the page-level error recovery path.
+ */
+export function SessionPhaseView({ state, sessionName, onOpenDiagnostics }: PhaseProps) {
+  const title =
+    state === 'preparing'
+      ? 'Analysis preparing'
+      : state === 'cancelled'
+        ? 'Session cancelled'
+        : 'Analysis unavailable'
+
+  const testId =
+    state === 'preparing'
+      ? 'rh-preparing'
+      : state === 'cancelled'
+        ? 'rh-cancelled'
+        : 'rh-unavailable'
+
+  return (
+    <div className="rh-presession" data-testid={testId}>
+      <section className="rh-presession-band">
+        <span className="rh-presession-eyebrow mono">{sessionStateLabelEyebrow(state)}</span>
+        <h2 className="rh-presession-title">{title}</h2>
+        <p className="rh-presession-sub">
+          {sessionName}: {sessionStateDescription(state)}
+        </p>
+        {state === 'preparing' && (
+          <p className="rh-presession-sub">
+            Check back shortly, or open Diagnostics if you need raw dataset coverage.
+          </p>
+        )}
+        {onOpenDiagnostics && (state === 'preparing' || state === 'unavailable') && (
+          <div className="rh-empty-actions" style={{ marginTop: 'var(--s4)' }}>
+            <button type="button" className="rh-empty-action" onClick={onOpenDiagnostics}>
+              Open Diagnostics
+            </button>
+          </div>
+        )}
+      </section>
+    </div>
+  )
+}
+
+function sessionStateLabelEyebrow(state: PhaseProps['state']): string {
+  if (state === 'preparing') return 'Settling'
+  if (state === 'cancelled') return 'Cancelled'
+  return 'Unavailable'
+}
+
+interface PartialBannerProps {
+  onOpenDiagnostics?: () => void
+}
+
+export function PartialAnalysisBanner({ onOpenDiagnostics }: PartialBannerProps) {
+  return (
+    <div className="rh-partial-banner" data-testid="rh-partial-banner" role="status">
+      <span>Partial analysis — some datasets are still missing.</span>
+      {onOpenDiagnostics && (
+        <button type="button" className="rh-partial-banner-link" onClick={onOpenDiagnostics}>
+          Diagnostics
+        </button>
+      )}
+    </div>
+  )
+}

frontend/src/components/RaceStoryCanvas.tsx

@@ -1,6 +1,36 @@
-import { useState, useMemo, useRef, useCallback } from 'react'
+import { useEffect, useMemo, useRef, useState } from 'react'
-import type { EnrichedResult, EnrichedGrid, PositionSample, Lap, Session } from '../types'
+import { useQuery } from '@tanstack/react-query'
+import { LineChart } from 'lucide-react'
+import type { Driver, EnrichedResult, EnrichedGrid, PositionSample, Lap, Meeting, Session, Chapter } from '../types'
+import { fetchReplayFrames, fetchTrackOutline } from '../api'
+import { ReplayTrackMap } from './ReplayTrackMap'
+import { ChapterStrip } from './ChapterStrip'
+import { EmptyStateCard } from './EmptyStateCard'
 import { gridDelta, gridDeltaClass, formatDuration, formatGap } from '../utils'
+import {
+  chapterBandFill,
+  chapterEndScrub,
+  chapterStartScrub,
+  chapterTourDurations,
+  deCollideYPositions,
+  decimatedPositionLabels,
+} from '../lib/chapters'
+import { isReplayMapAvailable } from '../lib/replayMap'
+import '../styles/race-story.css'
+
+const CHAPTER_TOUR_MS = 90_000
+const CHART_W = 640
+const CHART_H = 180
+const CHART_PL = 40
+const CHART_PR = 48
+const CHART_PT = 8
+const CHART_PB = 20
+
+interface ChartTiming {
+  tMin: number
+  tMax: number
+  tRange: number
+}
 
 interface Props {
   data: {
@@ -12,38 +42,256 @@ interface Props {
     race_control?: any[]
     pit_stops?: any[]
     session?: Session
+    meeting?: Meeting
+    drivers?: Driver[]
+    chapters?: Chapter[]
   }
 }
 
+/**
+ * Position samples are recorded for the entire session, including the pre-race
+ * grid period.  Use the winning driver's laps to define the race window so
+ * that the x-axis starts at lights-out rather than at the earliest sample.
+ */
+function raceChartTiming(
+  positions: PositionSample[],
+  laps: Lap[],
+  results: EnrichedResult[],
+): ChartTiming | null {
+  const positionTimes = positions
+    .map((position) => new Date(position.date).getTime())
+    .filter(Number.isFinite)
+  if (positionTimes.length === 0) return null
+
+  const fallbackMin = Math.min(...positionTimes)
+  const fallbackMax = Math.max(...positionTimes)
+  const fallback = {
+    tMin: fallbackMin,
+    tMax: fallbackMax,
+    tRange: Math.max(fallbackMax - fallbackMin, 1),
+  }
+
+  const winner = results.find((result) => result.position === 1)
+  if (!winner) return fallback
+
+  const winnerLaps = laps
+    .filter((lap) => lap.driver_number === winner.driver_number && lap.lap_number > 0)
+    .map((lap) => ({ ...lap, start: new Date(lap.date_start).getTime() }))
+    .filter((lap) => Number.isFinite(lap.start))
+    .sort((a, b) => a.lap_number - b.lap_number)
+  if (winnerLaps.length === 0) return fallback
+
+  const firstLap = winnerLaps[0]
+  const lastLap = winnerLaps[winnerLaps.length - 1]
+  const finalLapDuration = lastLap.lap_duration ?? 0
+  const tMax = lastLap.start + (finalLapDuration > 0 ? finalLapDuration * 1000 : 0)
+  if (tMax <= firstLap.start) return fallback
+
+  return { tMin: firstLap.start, tMax, tRange: tMax - firstLap.start }
+}
+
 export function RaceStoryCanvas({ data }: Props) {
-  const { results, starting_grid: grid, positions, datasets, race_control = [], pit_stops = [], laps = [] } = data
+  const {
+    results,
+    starting_grid: grid,
+    positions,
+    datasets,
+    race_control = [],
+    pit_stops = [],
+    laps = [],
+    session,
+    meeting,
+    drivers = [],
+    chapters = [],
+  } = data
   const hasPositions = datasets['positions']?.status === 'available'
 
   const [scrubTime, setScrubTime] = useState<number | null>(null)
   const [hoverDriver, setHoverDriver] = useState<number | null>(null)
+  const [mapOpen, setMapOpen] = useState(false)
+  const [isPlaying, setIsPlaying] = useState(false)
+  const [playbackSpeed, setPlaybackSpeed] = useState(10)
+  const [chapterTourActive, setChapterTourActive] = useState(false)
+  const [tourChapterIndex, setTourChapterIndex] = useState<number | null>(null)
+  const [selectedChapterIndex, setSelectedChapterIndex] = useState<number | null>(null)
   const svgRef = useRef<SVGSVGElement>(null)
+  const tourRef = useRef({ chapterIndex: 0, startedAt: 0, durationMs: 0, startScrub: 0, endScrub: 0 })
 
-  // Position Evolution Chart Logic
+  const chartTiming = useMemo(() => raceChartTiming(positions, laps, results), [laps, positions, results])
-  const allTimes = useMemo(() => [...new Set(positions.map((p) => p.date))].sort(), [positions])
+  const hasChartData = hasPositions && chartTiming !== null
-  const hasChartData = hasPositions && allTimes.length > 0
+  const circuitKey = session?.circuit_key ?? meeting?.circuit_key ?? 0
+  const outlineYear = meeting?.year ?? (session?.date_start ? new Date(session.date_start).getFullYear() : 0)
+  const canProbeMap = Boolean(session?.session_key) && circuitKey > 0 && outlineYear > 0
+
+  const replayQuery = useQuery({
+    queryKey: ['replay-frames', session?.session_key, 5000],
+    queryFn: () => fetchReplayFrames(session!.session_key, 5000),
+    enabled: canProbeMap,
+  })
+  const outlineQuery = useQuery({
+    queryKey: ['track-outline', circuitKey, outlineYear],
+    queryFn: () => fetchTrackOutline(circuitKey, outlineYear),
+    enabled: canProbeMap,
+  })
+
+  const mapProbeSettled = !canProbeMap || (!replayQuery.isLoading && !outlineQuery.isLoading)
+  const mapAvailable = useMemo(
+    () =>
+      canProbeMap &&
+      isReplayMapAvailable(
+        replayQuery.data,
+        outlineQuery.data,
+        replayQuery.isError || outlineQuery.isError,
+      ),
+    [canProbeMap, outlineQuery.data, outlineQuery.isError, replayQuery.data, replayQuery.isError],
+  )
+  const showMapPanel = mapOpen && mapAvailable
+
+  useEffect(() => {
+    if (!mapAvailable && mapOpen) {
+      setMapOpen(false)
+    }
+  }, [mapAvailable, mapOpen])
+
+  useEffect(() => {
+    if (!isPlaying || !chartTiming) return
+
+    let frame = 0
+    let last = performance.now()
+    const tick = (now: number) => {
+      const delta = now - last
+      last = now
+      setScrubTime((current) => {
+        const next = Math.min(1, (current ?? 0) + (delta * playbackSpeed) / chartTiming.tRange)
+        if (next >= 1) {
+          setIsPlaying(false)
+        }
+        return next
+      })
+      frame = requestAnimationFrame(tick)
+    }
+
+    frame = requestAnimationFrame(tick)
+    return () => cancelAnimationFrame(frame)
+  }, [chartTiming, isPlaying, playbackSpeed])
+
+  const stopChapterTour = () => {
+    setChapterTourActive(false)
+    setTourChapterIndex(null)
+  }
+
+  const jumpToChapter = (index: number, scrub: number) => {
+    setIsPlaying(false)
+    stopChapterTour()
+    setSelectedChapterIndex(index)
+    setScrubTime(scrub)
+  }
+
+  const clearChapterSelection = () => {
+    setSelectedChapterIndex(null)
+  }
+
+  const toggleChapterTour = () => {
+    if (chapterTourActive) {
+      stopChapterTour()
+      return
+    }
+    if (!chartTiming || chapters.length === 0) return
+    setIsPlaying(false)
+    setSelectedChapterIndex(null)
+    setChapterTourActive(true)
+    setTourChapterIndex(0)
+    const startScrub = chapterStartScrub(chapters[0], chartTiming.tMin, chartTiming.tRange) ?? 0
+    setScrubTime(startScrub)
+    const durations = chapterTourDurations(chapters, CHAPTER_TOUR_MS)
+    tourRef.current = {
+      chapterIndex: 0,
+      startedAt: performance.now(),
+      durationMs: durations[0] ?? CHAPTER_TOUR_MS / chapters.length,
+      startScrub,
+      endScrub: chapterEndScrub(chapters[0], chartTiming.tMin, chartTiming.tRange) ?? startScrub,
+    }
+  }
+
+  useEffect(() => {
+    if (!chapterTourActive || !chartTiming || chapters.length === 0) return
+
+    let frame = 0
+    const tick = (now: number) => {
+      const state = tourRef.current
+      const elapsed = now - state.startedAt
+      const progress = Math.min(1, elapsed / Math.max(state.durationMs, 1))
+      const scrub = state.startScrub + (state.endScrub - state.startScrub) * progress
+      setScrubTime(scrub)
+      setTourChapterIndex(state.chapterIndex)
+
+      if (progress >= 1) {
+        const nextIndex = state.chapterIndex + 1
+        if (nextIndex >= chapters.length) {
+          stopChapterTour()
+          return
+        }
+        const durations = chapterTourDurations(chapters, CHAPTER_TOUR_MS)
+        const startScrub = chapterStartScrub(chapters[nextIndex], chartTiming.tMin, chartTiming.tRange) ?? 0
+        const endScrub = chapterEndScrub(chapters[nextIndex], chartTiming.tMin, chartTiming.tRange) ?? startScrub
+        tourRef.current = {
+          chapterIndex: nextIndex,
+          startedAt: now,
+          durationMs: durations[nextIndex] ?? CHAPTER_TOUR_MS / chapters.length,
+          startScrub,
+          endScrub,
+        }
+      }
+      frame = requestAnimationFrame(tick)
+    }
+
+    frame = requestAnimationFrame(tick)
+    return () => cancelAnimationFrame(frame)
+  }, [chapterTourActive, chartTiming, chapters])
+
+  useEffect(() => {
+    if (!chapterTourActive) return
+    const onKeyDown = (event: KeyboardEvent) => {
+      if (event.key === 'Escape') {
+        stopChapterTour()
+      }
+    }
+    window.addEventListener('keydown', onKeyDown)
+    return () => window.removeEventListener('keydown', onKeyDown)
+  }, [chapterTourActive])
+
+  const replayTMs = useMemo(() => {
+    const replay = replayQuery.data
+    const frames = replay?.frames ?? []
+    if (frames.length === 0) return 0
+    const lastFrameT = frames[frames.length - 1].t
+    const progress = scrubTime ?? 0
+    if (!chartTiming || !replay?.start_time) {
+      return Math.max(0, Math.min(lastFrameT, Math.round(progress * lastFrameT)))
+    }
+    const replayStart = new Date(replay.start_time).getTime()
+    const chartTime = chartTiming.tMin + progress * chartTiming.tRange
+    return Math.max(0, Math.min(lastFrameT, Math.round(chartTime - replayStart)))
+  }, [chartTiming, replayQuery.data, scrubTime])
 
   let chartContent = null
   let displayResults = results
 
-  if (hasChartData) {
+  if (hasChartData && chartTiming) {
-    const tMin = new Date(allTimes[0]).getTime()
+    const { tMin, tRange } = chartTiming
-    const tMax = new Date(allTimes[allTimes.length - 1]).getTime()
+    const normaliseTime = (time: number) => Math.max(0, Math.min(1, (time - tMin) / tRange))
-    const tRange = Math.max(tMax - tMin, 1)
 
     const byDriver = new Map<number, Array<{ t: number; pos: number }>>()
     for (const p of positions) {
+      const time = new Date(p.date).getTime()
+      if (!Number.isFinite(time)) continue
       if (!byDriver.has(p.driver_number)) byDriver.set(p.driver_number, [])
       byDriver.get(p.driver_number)!.push({
-        t: (new Date(p.date).getTime() - tMin) / tRange,
+        t: normaliseTime(time),
         pos: p.position,
       })
     }
-    const dnfSet = new Set(results.filter(r => r.dnf || r.dns || r.dsq).map(r => r.driver_number))
+    const dnfSet = new Set(results.filter((r) => r.dnf || r.dns || r.dsq).map((r) => r.driver_number))
     for (const [dNum, samples] of byDriver.entries()) {
       samples.sort((a, b) => a.t - b.t)
       if (samples.length > 0 && !dnfSet.has(dNum)) {
@@ -51,16 +299,16 @@ export function RaceStoryCanvas({ data }: Props) {
       }
     }
 
-    const getInterpPos = (samples: {t: number, pos: number}[], t: number) => {
+    const getInterpPos = (samples: { t: number; pos: number }[], t: number) => {
       if (!samples || samples.length === 0) return null
       if (t <= samples[0].t) return samples[0].pos
       if (t >= samples[samples.length - 1].t) return samples[samples.length - 1].pos
       for (let i = 0; i < samples.length - 1; i++) {
-        if (samples[i].t <= t && samples[i+1].t >= t) {
+        if (samples[i].t <= t && samples[i + 1].t >= t) {
-          const dt = samples[i+1].t - samples[i].t
+          const dt = samples[i + 1].t - samples[i].t
           if (dt === 0) return samples[i].pos
           const frac = (t - samples[i].t) / dt
-          return samples[i].pos + (samples[i+1].pos - samples[i].pos) * frac
+          return samples[i].pos + (samples[i + 1].pos - samples[i].pos) * frac
         }
       }
       return null
@@ -84,43 +332,46 @@ export function RaceStoryCanvas({ data }: Props) {
     const maxPos = Math.max(...positions.map((p) => p.position), results.length, 2)
     const colorByDriver = new Map(results.map((r) => [r.driver_number, r.team_colour]))
     const acronymByDriver = new Map(results.map((r) => [r.driver_number, r.name_acronym]))
+    const positionLabels = decimatedPositionLabels(maxPos)
 
-    const W = 640
+    const W = CHART_W
-    const H = 180
+    const H = CHART_H
-    const PL = 40
+    const PL = CHART_PL
-    const PR = 48
+    const PR = CHART_PR
-    const PT = 8
+    const PT = CHART_PT
-    const PB = 20
+    const PB = CHART_PB
     const plotW = W - PL - PR
     const plotH = H - PT - PB
 
     const toX = (t: number) => PL + t * plotW
     const toY = (pos: number) => PT + ((pos - 1) / Math.max(maxPos - 1, 1)) * plotH
 
-    const winner = results.find(r => r.position === 1)
+    const winner = results.find((r) => r.position === 1)
-    const winnerLaps = winner ? laps.filter(l => l.driver_number === winner.driver_number) : []
+    const winnerLaps = winner ? laps.filter((l) => l.driver_number === winner.driver_number) : []
-    const lapTicks: { lap: number, t: number }[] = []
+    const lapTicks: { lap: number; t: number }[] = []
     const lapInterval = winnerLaps.length < 30 ? 5 : 10
-    
+
-    for (const lap of winnerLaps) {
+    for (let i = 0; i < winnerLaps.length; i++) {
+      const lap = winnerLaps[i]
       if (lap.lap_number > 0 && lap.lap_number % lapInterval === 0) {
-        const t = (new Date(lap.date_start).getTime() - tMin) / tRange
+        const lapStart = new Date(lap.date_start).getTime()
-        if (t >= 0 && t <= 1) {
+        const nextLapStart = winnerLaps[i + 1] ? new Date(winnerLaps[i + 1].date_start).getTime() : NaN
-          lapTicks.push({ lap: lap.lap_number, t })
+        const lapEnd = lap.lap_duration && lap.lap_duration > 0
-        }
+          ? lapStart + lap.lap_duration * 1000
+          : nextLapStart
+        if (Number.isFinite(lapEnd)) lapTicks.push({ lap: lap.lap_number, t: normaliseTime(lapEnd) })
       }
     }
 
-    // Safety Car / VSC periods
     const scPeriods: { start: number; end: number | null; type: 'SC' | 'VSC' }[] = []
     let activeSC: { start: number; type: 'SC' | 'VSC' } | null = null
     const rc = [...race_control].sort((a, b) => new Date(a.date).getTime() - new Date(b.date).getTime())
-    
+
     for (const msg of rc) {
       const t = new Date(msg.date).getTime()
       const m = msg.message?.toUpperCase() || ''
       const cat = msg.category?.toUpperCase() || ''
-      
+
       if (m.includes('VIRTUAL SAFETY CAR DEPLOYED') || cat === 'VIRTUALSAFETYCAR') {
         if (!activeSC) activeSC = { start: t, type: 'VSC' }
       } else if (m.includes('SAFETY CAR DEPLOYED') || cat === 'SAFETYCAR') {
@@ -136,23 +387,73 @@ export function RaceStoryCanvas({ data }: Props) {
       scPeriods.push({ start: activeSC.start, end: null, type: activeSC.type })
     }
 
+    const chapterBands = chapters
+      .map((chapter, index) => {
+        const startT = chapterStartScrub(chapter, tMin, tRange)
+        const endT = chapterEndScrub(chapter, tMin, tRange)
+        if (startT === null) return null
+        const end = endT ?? startT
+        return {
+          key: `${chapter.kind}-${index}`,
+          start: Math.min(startT, end),
+          end: Math.max(startT, end),
+          fill: chapterBandFill(chapter.kind),
+        }
+      })
+      .filter((band): band is NonNullable<typeof band> => band !== null)
+
+    const labelCandidates = Array.from(byDriver.entries())
+      .map(([dNum, samples]) => {
+        const last = samples[samples.length - 1]
+        if (!last) return null
+        return { key: dNum, y: toY(last.pos) }
+      })
+      .filter((item): item is { key: number; y: number } => item !== null)
+    const labelYByDriver = deCollideYPositions(labelCandidates, 12)
+
     const handlePointerMove = (e: React.PointerEvent<SVGRectElement>) => {
+      setIsPlaying(false)
+      stopChapterTour()
+      clearChapterSelection()
       if (!svgRef.current) return
       const rect = svgRef.current.getBoundingClientRect()
-      const x = e.clientX - rect.left
+      if (rect.width <= 0) return
+      // Pointer coordinates are CSS pixels; convert them to the SVG viewBox
+      // before comparing with the fixed chart margins and plot width.
+      const x = ((e.clientX - rect.left) / rect.width) * W
       const t = Math.max(0, Math.min(1, (x - PL) / plotW))
       setScrubTime(t)
     }
 
     chartContent = (
-      <div className="rs-chart-container scroll-x" data-testid="position-chart">
+      <div
+        className={`rs-chart-container scroll-x${showMapPanel ? '' : ' rs-chart-container--full'}`}
+        data-testid="position-chart"
+      >
         <svg
           ref={svgRef}
+          className="rs-position-chart-svg"
           viewBox={`0 0 ${W} ${H}`}
-          style={{ width: '100%', minWidth: 280, maxWidth: W, display: 'block' }}
           role="img"
           aria-label="Position evolution chart"
         >
+          {chapterBands.map((band) => {
+            const x1 = toX(Math.max(0, band.start))
+            const x2 = toX(Math.min(1, band.end))
+            if (x2 <= PL || x1 >= W - PR) return null
+            return (
+              <rect
+                key={band.key}
+                x={x1}
+                y={PT}
+                width={Math.max(0, x2 - x1)}
+                height={plotH}
+                fill={band.fill}
+                data-testid="chapter-band"
+              />
+            )
+          })}
+
           {scPeriods.map((sc, i) => {
             const startT = (sc.start - tMin) / tRange
             const endT = sc.end ? (sc.end - tMin) / tRange : 1
@@ -171,33 +472,41 @@ export function RaceStoryCanvas({ data }: Props) {
             )
           })}
 
-          {Array.from({ length: maxPos }, (_, i) => i + 1).map((pos) => (
+          {positionLabels.map((pos) => (
             <g key={pos}>
               <line
                 x1={PL}
                 x2={W - PR}
                 y1={toY(pos)}
                 y2={toY(pos)}
-                stroke="var(--border)"
+                className="rs-chart-grid-line"
-                strokeWidth={0.5}
               />
               <text
                 x={PL - 4}
                 y={toY(pos) + 4}
                 textAnchor="end"
-                fill="var(--text-3)"
+                className="rs-chart-axis-label"
-                fontSize={8}
-                fontFamily="var(--f-mono)"
               >
                 P{pos}
               </text>
             </g>
           ))}
 
-          {lapTicks.map(tick => (
+          {lapTicks.map((tick) => (
             <g key={`lap-${tick.lap}`}>
-              <line x1={toX(tick.t)} x2={toX(tick.t)} y1={H - PB} y2={H - PB + 4} stroke="var(--border)" strokeWidth={1} />
+              <line
-              <text x={toX(tick.t)} y={H - PB + 14} textAnchor="middle" fill="var(--text-3)" fontSize={9} fontFamily="var(--f-mono)">
+                x1={toX(tick.t)}
+                x2={toX(tick.t)}
+                y1={H - PB}
+                y2={H - PB + 4}
+                className="rs-chart-lap-tick"
+              />
+              <text
+                x={toX(tick.t)}
+                y={H - PB + 14}
+                textAnchor="middle"
+                className="rs-chart-axis-label"
+              >
                 L{tick.lap}
               </text>
             </g>
@@ -210,11 +519,12 @@ export function RaceStoryCanvas({ data }: Props) {
             const last = samples[samples.length - 1]
             const isHovered = hoverDriver === dNum
             const isFaded = hoverDriver !== null && !isHovered
+            const labelY = last ? (labelYByDriver.get(dNum) ?? toY(last.pos)) : 0
 
-            const driverPits = pit_stops.filter(p => p.driver_number === dNum)
+            const driverPits = pit_stops.filter((p) => p.driver_number === dNum)
 
             return (
-              <g 
+              <g
                 key={dNum}
                 style={{ opacity: isFaded ? 0.2 : 1, transition: 'opacity 0.2s' }}
                 onMouseEnter={() => setHoverDriver(dNum)}
@@ -230,30 +540,31 @@ export function RaceStoryCanvas({ data }: Props) {
                   className="rs-driver-line"
                   pathLength={1}
                 />
-                
+
                 {driverPits.map((p, i) => {
-                  const t = (new Date(p.date).getTime() - tMin) / tRange
+                  const time = new Date(p.date).getTime()
-                  if (t < 0 || t > 1) return null
+                  if (!Number.isFinite(time) || time < tMin || time > tMin + tRange) return null
+                  const t = normaliseTime(time)
                   const pos = getInterpPos(samples, t)
                   if (pos === null) return null
                   return (
-                    <circle 
+                    <circle
-                      key={`pit-${i}`} 
+                      key={`pit-${i}`}
-                      cx={toX(t)} 
+                      cx={toX(t)}
-                      cy={toY(pos)} 
+                      cy={toY(pos)}
-                      r={3} 
+                      r={3}
-                      fill="var(--bg)" 
+                      fill="var(--bg)"
-                      stroke={color} 
+                      stroke={color}
                       strokeWidth={2}
                       className="rs-pit-dot"
                     />
                   )
                 })}
-                
+
                 {last && (
                   <text
                     x={toX(last.t) + 6}
-                    y={toY(last.pos) + 4}
+                    y={labelY + 4}
                     fill={color}
                     fontSize={isHovered ? 11 : 9}
                     fontFamily="var(--f-mono)"
@@ -287,25 +598,110 @@ export function RaceStoryCanvas({ data }: Props) {
             width={plotW}
             height={plotH}
             fill="transparent"
+            data-testid="position-chart-interaction"
             onPointerMove={handlePointerMove}
-            onPointerLeave={() => setScrubTime(null)}
+            onPointerLeave={() => {
+              if (!isPlaying) {
+                clearChapterSelection()
+                setScrubTime(null)
+              }
+            }}
             style={{ cursor: 'crosshair', touchAction: 'none' }}
           />
         </svg>
+        <div className="rs-segmented-control" aria-label="Race replay controls" data-testid="replay-controls">
+          <button
+            type="button"
+            className={`rs-segment ${isPlaying ? 'active' : ''}`}
+            onClick={() => {
+              setScrubTime((current) => current ?? 0)
+              stopChapterTour()
+              clearChapterSelection()
+              setIsPlaying((current) => !current)
+            }}
+            aria-pressed={isPlaying}
+          >
+            {isPlaying ? 'Pause' : 'Play'}
+          </button>
+          <span className="rs-segment-divider" aria-hidden />
+          {[1, 10, 30].map((speed) => (
+            <button
+              key={speed}
+              type="button"
+              className={`rs-segment ${playbackSpeed === speed ? 'active' : ''}`}
+              onClick={() => setPlaybackSpeed(speed)}
+              aria-pressed={playbackSpeed === speed}
+            >
+              {speed}x
+            </button>
+          ))}
+          {mapProbeSettled && mapAvailable && (
+            <>
+              <span className="rs-segment-divider" aria-hidden />
+              <button
+                type="button"
+                className={`rs-segment ${mapOpen ? 'active' : ''}`}
+                onClick={() => setMapOpen((current) => !current)}
+                aria-pressed={mapOpen}
+                data-testid="replay-map-toggle"
+              >
+                Map
+              </button>
+            </>
+          )}
+        </div>
       </div>
     )
   }
 
   return (
     <div className="race-story-canvas">
-      {hasChartData ? (
+      {hasChartData && chartTiming && chapters.length > 0 && (
-        chartContent
+        <ChapterStrip
-      ) : (
+          chapters={chapters}
-        <div className="analysis-notice">
+          scrubTime={scrubTime}
-          <strong>Lap-by-lap positions not available.</strong> This session does not
+          tMin={chartTiming.tMin}
-          have ingested position samples in <code>/api/v1/race-hub</code>.
+          tRange={chartTiming.tRange}
-        </div>
+          tourActive={chapterTourActive}
+          tourChapterIndex={tourChapterIndex}
+          selectedChapterIndex={selectedChapterIndex}
+          onChapterClick={jumpToChapter}
+          onTourToggle={toggleChapterTour}
+        />
       )}
+      <div className={`rs-replay-shell${showMapPanel ? ' rs-replay-shell--split' : ''}`}>
+        <div className="rs-replay-main">
+          {hasChartData ? (
+            chartContent
+          ) : (
+            <EmptyStateCard
+              icon={LineChart}
+              title="Lap-by-lap positions not available"
+              hint={
+                <>
+                  This session does not have ingested position samples in{' '}
+                  <code>/api/v1/race-hub</code>.
+                </>
+              }
+              testId="race-story-no-positions"
+              className="race-story-empty-card"
+            />
+          )}
+        </div>
+        {showMapPanel && (
+          <div className="rs-replay-map-slot" data-testid="replay-map-slot">
+            <ReplayTrackMap
+              outline={outlineQuery.data}
+              replay={replayQuery.data}
+              tMs={replayTMs}
+              drivers={drivers}
+              results={results}
+              loading={outlineQuery.isLoading || replayQuery.isLoading}
+              error={outlineQuery.isError || replayQuery.isError}
+            />
+          </div>
+        )}
+      </div>
 
       {displayResults.length > 0 && (
         <div className="rs-field-list">
@@ -313,30 +709,29 @@ export function RaceStoryCanvas({ data }: Props) {
             const gridPos = grid.find((g) => g.driver_number === r.driver_number)?.position ?? 0
             const currentPos = scrubTime !== null ? i + 1 : r.position
             const isWinner = i === 0 && r.position === 1
-            const pClass = currentPos === 1 ? 'rs-pos-p1' : currentPos === 2 ? 'rs-pos-p2' : currentPos === 3 ? 'rs-pos-p3' : ''
+            const pClass =
-            
+              currentPos === 1 ? 'rs-pos-p1' : currentPos === 2 ? 'rs-pos-p2' : currentPos === 3 ? 'rs-pos-p3' : ''
+
             let currentPoints: number | string = r.points
             if (scrubTime !== null) {
               const isSprint = data.session?.session_type?.toLowerCase().includes('sprint')
               const ptsArray = isSprint ? [8, 7, 6, 5, 4, 3, 2, 1] : [25, 18, 15, 12, 10, 8, 6, 4, 2, 1]
               currentPoints = currentPos <= ptsArray.length ? ptsArray[currentPos - 1] : 0
             }
-            
+
             return (
-              <div 
+              <div
-                key={r.driver_number} 
+                key={r.driver_number}
                 className={`rs-driver-row ${hoverDriver === r.driver_number ? 'rs-driver-row-hover' : ''}`}
                 onMouseEnter={() => setHoverDriver(r.driver_number)}
                 onMouseLeave={() => setHoverDriver(null)}
               >
                 <div className="rs-driver-left">
-                  <div className={`rs-pos-col ${pClass}`}>
+                  <div className={`rs-pos-col ${pClass}`}>{currentPos}</div>
-                    {currentPos}
-                  </div>
                   <div className="rs-driver-cell">
-                    <div 
+                    <div
-                      className="rs-driver-color" 
+                      className="rs-driver-color"
-                      style={{ background: r.team_colour ? `#${r.team_colour}` : 'var(--border)' }} 
+                      style={{ background: r.team_colour ? `#${r.team_colour}` : 'var(--border)' }}
                     />
                     <div className="rs-driver-identity">
                       <span className="rs-driver-name">{r.name_acronym || r.driver_number}</span>
@@ -354,12 +749,12 @@ export function RaceStoryCanvas({ data }: Props) {
                     </span>
                     <span className="rs-metric-label">Grid</span>
                   </div>
-                  
+
                   <div className="rs-metric" style={{ width: '80px', opacity: scrubTime !== null ? 0.3 : 1 }}>
                     <span>{isWinner ? formatDuration(r.duration) : formatGap(r.gap_to_leader)}</span>
                     <span className="rs-metric-label">{isWinner ? 'Time' : 'Gap'}</span>
                   </div>
-                  
+
                   <div className="rs-metric" style={{ width: '40px' }}>
                     <span style={{ color: Number(currentPoints) > 0 ? 'var(--text)' : 'var(--text-3)' }}>
                       {currentPoints}

frontend/src/components/ReplayTrackMap.tsx

@@ -0,0 +1,159 @@
+import { useMemo, useState } from 'react'
+import { Loader2, MapPin, Satellite } from 'lucide-react'
+import type { Driver, EnrichedResult, ReplayFramesResponse, TrackOutline } from '../types'
+import { buildOutlinePath } from '../lib/trackmap'
+import { interpolateReplayCars, replayCarToSvg } from '../lib/replay'
+import { EmptyStateCard } from './EmptyStateCard'
+import '../styles/replay-map.css'
+
+interface Props {
+  outline?: TrackOutline | null
+  replay?: ReplayFramesResponse | null
+  tMs: number
+  drivers: Driver[]
+  results: EnrichedResult[]
+  loading?: boolean
+  error?: boolean
+}
+
+export function ReplayTrackMap({
+  outline,
+  replay,
+  tMs,
+  drivers,
+  results,
+  loading = false,
+  error = false,
+}: Props) {
+  const [pinned, setPinned] = useState<string | null>(null)
+  const outlinePath = useMemo(() => buildOutlinePath(outline?.points ?? []), [outline])
+  const driverInfo = useMemo(() => {
+    const info = new Map<string, { label: string; color: string }>()
+    for (const driver of drivers) {
+      info.set(String(driver.driver_number), {
+        label: driver.name_acronym || String(driver.driver_number),
+        color: normalizeColor(driver.team_colour),
+      })
+    }
+    for (const result of results) {
+      const key = String(result.driver_number)
+      if (!info.has(key)) {
+        info.set(key, {
+          label: result.name_acronym || key,
+          color: normalizeColor(result.team_colour),
+        })
+      }
+    }
+    return info
+  }, [drivers, results])
+
+  const cars = useMemo(() => {
+    if (!outline?.bounds || !replay?.frames?.length) return []
+    const positions = interpolateReplayCars(replay.frames, tMs)
+    return Object.entries(positions)
+      .map(([number, car]) => ({
+        number,
+        svg: replayCarToSvg(car, outline.bounds),
+        info: driverInfo.get(number),
+      }))
+      .sort((a, b) => Number(a.number) - Number(b.number))
+  }, [driverInfo, outline?.bounds, replay?.frames, tMs])
+
+  if (loading) {
+    return (
+      <section className="replay-map-panel" data-testid="replay-track-map">
+        <EmptyStateCard
+          icon={Loader2}
+          title="Loading replay map"
+          hint="Fetching track outline and historical GPS frames."
+          testId="replay-map-loading"
+          className="replay-map-empty-card"
+        />
+      </section>
+    )
+  }
+
+  if (error) {
+    return (
+      <section className="replay-map-panel" data-testid="replay-track-map">
+        <EmptyStateCard
+          icon={Satellite}
+          title="Replay GPS unavailable"
+          hint="This session does not have ingested location samples for the replay map."
+          testId="replay-map-error"
+          className="replay-map-empty-card"
+        />
+      </section>
+    )
+  }
+
+  if (!outline || !outlinePath) {
+    return (
+      <section className="replay-map-panel" data-testid="replay-track-map">
+        <EmptyStateCard
+          icon={MapPin}
+          title="Track outline unavailable"
+          hint="Circuit GPS outline data is missing for this session."
+          testId="replay-map-no-outline"
+          className="replay-map-empty-card"
+        />
+      </section>
+    )
+  }
+
+  if (!replay?.frames?.length || cars.length === 0) {
+    return (
+      <section className="replay-map-panel" data-testid="replay-track-map">
+        <EmptyStateCard
+          icon={Satellite}
+          title="Historical GPS unavailable"
+          hint="Fewer than two replay frames were returned for this session."
+          testId="replay-map-no-frames"
+          className="replay-map-empty-card"
+        />
+      </section>
+    )
+  }
+
+  return (
+    <section className="replay-map-panel" data-testid="replay-track-map">
+      <div className="replay-map-stage">
+        <svg className="replay-map-svg" viewBox="0 0 100 100" role="img" aria-label="Replay track map">
+          <path className="replay-map-outline-shadow" d={outlinePath} />
+          <path className="replay-map-outline" d={outlinePath} />
+          {cars.map((car) => {
+            const label = car.info?.label ?? car.number
+            const selected = pinned === car.number
+            return (
+              <g
+                key={car.number}
+                role="button"
+                tabIndex={0}
+                aria-label={`${label} replay position`}
+                className={`replay-car ${selected ? 'replay-car-pinned' : ''}`}
+                transform={`translate(${car.svg.x.toFixed(2)} ${car.svg.y.toFixed(2)})`}
+                onClick={() => setPinned(selected ? null : car.number)}
+                onKeyDown={(event) => {
+                  if (event.key === 'Enter' || event.key === ' ') {
+                    event.preventDefault()
+                    setPinned(selected ? null : car.number)
+                  }
+                }}
+              >
+                <title>{label}</title>
+                <circle r="2.7" fill={car.info?.color ?? '#777777'} />
+                <text y="0.85">{label}</text>
+              </g>
+            )
+          })}
+        </svg>
+      </div>
+    </section>
+  )
+}
+
+function normalizeColor(color: string | undefined): string {
+  const raw = color?.trim()
+  if (!raw) return '#777777'
+  return raw.startsWith('#') ? raw : `#${raw}`
+}

frontend/src/components/RivalryCompare.tsx

@@ -0,0 +1,271 @@
+import { useMemo, useState } from 'react'
+import type { ChampHubDriver, ChampionshipHub } from '../types'
+import { teamColor } from '../utils'
+import { gapSeries, h2hTally, lastRounds } from '../lib/rivalry'
+import '../styles/rivalry.css'
+
+const PAD_L = 48
+const PAD_T = 16
+const PLOT_W = 882
+const PLOT_H = 316
+const GAP_PLOT_H = 200
+
+function fmtPts(n: number): string {
+  return Number.isInteger(n) ? String(n) : n.toFixed(1)
+}
+
+/** Up to ~7 evenly spaced round labels, always including the last round. */
+function xTicks(n: number, labels: string[], x: (i: number) => number): { x: number; label: string }[] {
+  const step = Math.max(1, Math.ceil(n / 7))
+  const ticks: { x: number; label: string }[] = []
+  for (let i = 0; i < n; i += step) {
+    ticks.push({ x: x(i), label: labels[i] ?? `R${i + 1}` })
+  }
+  const last = labels[n - 1] ?? `R${n}`
+  if (ticks[ticks.length - 1]?.label !== last) {
+    ticks.push({ x: x(n - 1), label: last })
+  }
+  return ticks
+}
+
+function polyline(values: number[], x: (i: number) => number, y: (v: number) => number): string {
+  return values.map((v, i) => `${x(i).toFixed(1)},${y(v).toFixed(1)}`).join(' ')
+}
+
+interface PickerProps {
+  id: 'a' | 'b'
+  label: string
+  drivers: ChampHubDriver[]
+  value: number
+  color: string
+  onChange: (driverNumber: number) => void
+}
+
+function DriverPicker({ id, label, drivers, value, color, onChange }: PickerProps) {
+  return (
+    <label className="rivalry-picker">
+      <span className="rivalry-picker-label">{label}</span>
+      <select
+        className="rivalry-picker-select"
+        style={{ borderLeft: `3px solid ${color}` }}
+        value={value}
+        data-testid={`rivalry-pick-${id}`}
+        onChange={(e) => onChange(Number(e.target.value))}
+      >
+        {drivers.map((d) => (
+          <option key={d.driver_number} value={d.driver_number}>
+            {d.name_acronym} · {d.full_name}
+          </option>
+        ))}
+      </select>
+    </label>
+  )
+}
+
+export function RivalryCompare({ hub }: { hub: ChampionshipHub }) {
+  const { drivers } = hub
+  const [pickA, setPickA] = useState<number | null>(null)
+  const [pickB, setPickB] = useState<number | null>(null)
+
+  // Default to the top two in the standings; fall back there if a picked
+  // driver disappears (e.g. season switch re-fetches the hub).
+  const a = drivers.find((d) => d.driver_number === pickA) ?? drivers[0]
+  const b = drivers.find((d) => d.driver_number === pickB) ?? drivers[1]
+
+  const tally = useMemo(
+    () => (a && b ? h2hTally(a.round_positions ?? [], b.round_positions ?? [], hub.round_labels) : null),
+    [a, b, hub.round_labels],
+  )
+
+  if (drivers.length < 2) {
+    return (
+      <div className="champ-chart-empty" data-testid="champ-view-rivalry">
+        Need at least two drivers in the standings to compare a rivalry.
+      </div>
+    )
+  }
+
+  const colorA = teamColor(a.team_colour)
+  const colorB = teamColor(b.team_colour)
+  const sameTeam = a.team_name === b.team_name
+
+  const cumA = a.cumulative ?? []
+  const cumB = b.cumulative ?? []
+  const rounds = Math.min(cumA.length, cumB.length)
+  const gaps = gapSeries(cumA, cumB)
+  const lastGap = gaps[gaps.length - 1] ?? 0
+  const strip = tally ? lastRounds(tally, 5) : []
+
+  const pickers = (
+    <div className="rivalry-pickers">
+      <DriverPicker id="a" label="Driver A" drivers={drivers} value={a.driver_number} color={colorA} onChange={setPickA} />
+      <span className="rivalry-vs mono">vs</span>
+      <DriverPicker id="b" label="Driver B" drivers={drivers} value={b.driver_number} color={colorB} onChange={setPickB} />
+    </div>
+  )
+
+  if (rounds === 0) {
+    return (
+      <div className="rivalry" data-testid="champ-view-rivalry">
+        {pickers}
+        <div className="champ-chart-empty">
+          No completed rounds yet — the rivalry will appear after the first race.
+        </div>
+      </div>
+    )
+  }
+
+  // Points race scales.
+  const peak = Math.max(...cumA.slice(0, rounds), ...cumB.slice(0, rounds), 1)
+  const maxY = Math.max(50, Math.ceil(peak / 50) * 50)
+  const px = (i: number) => (rounds <= 1 ? PAD_L : PAD_L + (i * PLOT_W) / (rounds - 1))
+  const py = (v: number) => PAD_T + PLOT_H - (v / maxY) * PLOT_H
+  const pyGrid = [0, 0.25, 0.5, 0.75, 1].map((f) => ({ y: py(maxY * f), label: Math.round(maxY * f) }))
+  const pxGrid = xTicks(rounds, hub.round_labels, px)
+
+  // Gap scales: symmetric around zero.
+  const maxAbs = Math.max(10, Math.ceil(Math.max(...gaps.map(Math.abs), 1) / 10) * 10)
+  const gy = (v: number) => PAD_T + GAP_PLOT_H / 2 - (v / maxAbs) * (GAP_PLOT_H / 2)
+  const gyGrid = [maxAbs, 0, -maxAbs].map((v) => ({ y: gy(v), label: v > 0 ? `+${v}` : String(v) }))
+  const gxGrid = xTicks(rounds, hub.round_labels, px)
+
+  const gapLeader = lastGap === 0 ? null : lastGap > 0 ? a : b
+  const gapCaption = gapLeader
+    ? `${gapLeader.name_acronym} leads by ${fmtPts(Math.abs(lastGap))} pts after ${hub.round_labels[rounds - 1] ?? `R${rounds}`}.`
+    : 'Dead level on points.'
+
+  return (
+    <div className="rivalry" data-testid="champ-view-rivalry">
+      {pickers}
+
+      <div className="rivalry-h2h" data-testid="rivalry-h2h">
+        <div className="rivalry-h2h-score">
+          <span className="rivalry-h2h-code mono" style={{ color: colorA }}>
+            {a.name_acronym}
+          </span>
+          <span className="rivalry-h2h-num mono" data-testid="rivalry-h2h-num">
+            {tally ? `${tally.a}–${tally.b}` : '—'}
+          </span>
+          <span className="rivalry-h2h-code mono" style={{ color: colorB }}>
+            {b.name_acronym}
+          </span>
+        </div>
+        <span className="rivalry-h2h-meta">
+          Race head-to-head · {tally?.rounds.length ?? 0} round{(tally?.rounds.length ?? 0) === 1 ? '' : 's'} counted
+          {tally && tally.skipped > 0 ? ` · ${tally.skipped} skipped` : ''}
+        </span>
+        {strip.length > 0 && (
+          <div className="rivalry-strip" data-testid="rivalry-strip">
+            <span className="rivalry-strip-label">Last {strip.length}</span>
+            {strip.map((r) => (
+              <span className="rivalry-chip" key={r.round} title={`${r.label}: ${a.name_acronym} P${r.posA} · ${b.name_acronym} P${r.posB}`}>
+                <span className="rivalry-chip-round mono">{r.label}</span>
+                <span className="rivalry-chip-winner mono" style={{ color: r.winner === 'a' ? colorA : colorB }}>
+                  {r.winner === 'a' ? a.name_acronym : b.name_acronym}
+                </span>
+              </span>
+            ))}
+          </div>
+        )}
+      </div>
+
+      <section className="rivalry-section" data-testid="rivalry-points-race">
+        <div className="champ-chart-head">
+          <span className="champ-chart-title mono">
+            Points race — {a.name_acronym} vs {b.name_acronym}
+          </span>
+          <span className="champ-chart-meta">
+            Rounds 1–{rounds} · {hub.season}
+          </span>
+        </div>
+        <div className="champ-chart">
+          <svg viewBox="0 0 1000 380" className="champ-chart-svg" preserveAspectRatio="none">
+            {pyGrid.map((g) => (
+              <g key={g.label}>
+                <line x1={PAD_L} y1={g.y} x2={930} y2={g.y} stroke="var(--border)" strokeWidth="1" />
+                <text x={40} y={g.y + 4} textAnchor="end" className="champ-chart-axis">
+                  {g.label}
+                </text>
+              </g>
+            ))}
+            {pxGrid.map((g, i) => (
+              <text key={i} x={g.x} y={372} textAnchor="middle" className="champ-chart-axis">
+                {g.label}
+              </text>
+            ))}
+            {[
+              { slot: 'a', d: a, color: colorA, dash: '0', values: cumA.slice(0, rounds) },
+              { slot: 'b', d: b, color: colorB, dash: sameTeam ? '5 4' : '0', values: cumB.slice(0, rounds) },
+            ].map((s) => (
+              <g key={s.slot}>
+                <polyline
+                  points={polyline(s.values, px, py)}
+                  fill="none"
+                  stroke={s.color}
+                  strokeWidth="2.4"
+                  strokeDasharray={s.dash}
+                  strokeLinejoin="round"
+                  strokeLinecap="round"
+                />
+                <circle cx={px(s.values.length - 1)} cy={py(s.values[s.values.length - 1])} r="3" fill={s.color} />
+                <text
+                  x={px(s.values.length - 1) + 8}
+                  y={py(s.values[s.values.length - 1]) + 4}
+                  fill={s.color}
+                  className="champ-chart-label"
+                >
+                  {s.d.name_acronym}
+                </text>
+              </g>
+            ))}
+          </svg>
+        </div>
+      </section>
+
+      <section className="rivalry-section" data-testid="rivalry-gap">
+        <div className="champ-chart-head">
+          <span className="champ-chart-title mono">
+            Gap over season — {a.name_acronym} − {b.name_acronym}
+          </span>
+          <span className="champ-chart-meta">{gapCaption}</span>
+        </div>
+        <div className="champ-chart">
+          <svg viewBox="0 0 1000 250" className="champ-chart-svg" preserveAspectRatio="none">
+            {gyGrid.map((g) => (
+              <g key={g.label}>
+                <line
+                  x1={PAD_L}
+                  y1={g.y}
+                  x2={930}
+                  y2={g.y}
+                  stroke={g.label === '0' ? 'var(--border-2)' : 'var(--border)'}
+                  strokeWidth={g.label === '0' ? 1.5 : 1}
+                />
+                <text x={40} y={g.y + 4} textAnchor="end" className="champ-chart-axis">
+                  {g.label}
+                </text>
+              </g>
+            ))}
+            {gxGrid.map((g, i) => (
+              <text key={i} x={g.x} y={242} textAnchor="middle" className="champ-chart-axis">
+                {g.label}
+              </text>
+            ))}
+            <polyline
+              points={polyline(gaps, px, gy)}
+              fill="none"
+              stroke={colorA}
+              strokeWidth="2.4"
+              strokeLinejoin="round"
+              strokeLinecap="round"
+            />
+            <circle cx={px(gaps.length - 1)} cy={gy(lastGap)} r="3" fill={colorA} />
+          </svg>
+        </div>
+        <p className="rivalry-caption">
+          Above the zero line: {a.name_acronym} ahead. Below: {b.name_acronym} ahead.
+        </p>
+      </section>
+    </div>
+  )
+}

frontend/src/components/TabBar.tsx

@@ -8,15 +8,46 @@ export type Tab =
   | 'race_control'
   | 'data_status'
 
-const TABS: { id: Tab; label: string }[] = [
+interface TabDef {
-  { id: 'overview', label: 'Overview' },
+  id: Tab
-  { id: 'race_story', label: 'Race Story' },
+  label: string
-  { id: 'strategy', label: 'Strategy' },
+}
-  { id: 'compare', label: 'Compare' },
+
-  { id: 'lap_data', label: 'Lap Data' },
+interface TabGroup {
-  { id: 'conditions', label: 'Conditions' },
+  id: string
-  { id: 'race_control', label: 'Race Control' },
+  label: string
-  { id: 'data_status', label: 'Data Status' },
+  tabs: TabDef[]
+}
+
+// Fan-facing hierarchy: Story first, then Analysis, then Data/Context. Every
+// existing capability is preserved — only the grouping and ordering change.
+const TAB_GROUPS: TabGroup[] = [
+  {
+    id: 'story',
+    label: 'Story',
+    tabs: [
+      { id: 'overview', label: 'Overview' },
+      { id: 'race_story', label: 'Race Story' },
+    ],
+  },
+  {
+    id: 'analysis',
+    label: 'Analysis',
+    tabs: [
+      { id: 'strategy', label: 'Strategy' },
+      { id: 'compare', label: 'Compare' },
+      { id: 'lap_data', label: 'Lap Data' },
+    ],
+  },
+  {
+    id: 'context',
+    label: 'Data & Context',
+    tabs: [
+      { id: 'conditions', label: 'Conditions' },
+      { id: 'race_control', label: 'Race Control' },
+      { id: 'data_status', label: 'Diagnostics' },
+    ],
+  },
 ]
 
 interface Props {
@@ -26,17 +57,26 @@ interface Props {
 
 export function TabBar({ active, onChange }: Props) {
   return (
-    <div className="tab-bar" role="tablist">
+    <div className="tab-bar tab-bar-grouped" role="tablist" data-testid="rh-tabbar">
-      {TABS.map((t) => (
+      {TAB_GROUPS.map((group) => (
-        <button
+        <div key={group.id} className="tab-group" data-testid={`rh-tabgroup-${group.id}`}>
-          key={t.id}
+          <span className="tab-group-label mono" aria-hidden="true">
-          role="tab"
+            {group.label}
-          aria-selected={active === t.id}
+          </span>
-          className={`tab-btn${active === t.id ? ' active' : ''}`}
+          <div className="tab-group-btns">
-          onClick={() => onChange(t.id)}
+            {group.tabs.map((t) => (
-        >
+              <button
-          {t.label}
+                key={t.id}
-        </button>
+                role="tab"
+                aria-selected={active === t.id}
+                className={`tab-btn${active === t.id ? ' active' : ''}`}
+                onClick={() => onChange(t.id)}
+              >
+                {t.label}
+              </button>
+            ))}
+          </div>
+        </div>
       ))}
     </div>
   )

frontend/src/components/TeammateH2H.tsx

@@ -0,0 +1,55 @@
+import { teamColor } from '../utils'
+import '../styles/h2h.css'
+
+export interface TeammateH2HProps {
+  teamName: string
+  teamColour: string
+  driverATla: string
+  driverBTla: string
+  winsA: number
+  winsB: number
+  /** e.g. "+1" when more than two drivers share the team. */
+  extraNote?: string
+}
+
+export function TeammateH2H({
+  teamName,
+  teamColour,
+  driverATla,
+  driverBTla,
+  winsA,
+  winsB,
+  extraNote,
+}: TeammateH2HProps) {
+  const total = winsA + winsB || 1
+  const pctA = (winsA / total) * 100
+  const color = teamColor(teamColour)
+
+  return (
+    <div className="h2h-row" data-testid="teammate-h2h">
+      <div className="h2h-team">
+        <span className="h2h-team-name">{teamName}</span>
+        {extraNote ? <span className="h2h-extra mono">{extraNote}</span> : null}
+      </div>
+      <div className="h2h-bar-wrap">
+        <span className="h2h-tla h2h-tla--left mono">{driverATla}</span>
+        <div className="h2h-bar" data-testid="h2h-bar">
+          <span
+            className="h2h-bar-seg"
+            data-testid="h2h-bar-a"
+            style={{ width: `${pctA}%`, background: color }}
+          />
+          <span
+            className="h2h-bar-seg h2h-bar-seg--muted"
+            data-testid="h2h-bar-b"
+            style={{ width: `${100 - pctA}%`, background: color }}
+          />
+          <span className="h2h-score mono" data-testid="h2h-score">
+            {winsA}–{winsB}
+          </span>
+        </div>
+        <span className="h2h-tla h2h-tla--right mono">{driverBTla}</span>
+      </div>
+    </div>
+  )
+}

frontend/src/components/WeekendSwitcher.tsx

@@ -2,34 +2,37 @@ import { useEffect, useState } from 'react'
 import { useQuery } from '@tanstack/react-query'
 import { useNavigate } from '@tanstack/react-router'
 import { fetchLocalMeetings, fetchSeasons, fetchWeekend } from '../api'
-import { formatCoverageHint, sessionTypeAbbrev } from '../lib/coverage'
+import { sessionTypeAbbrev } from '../lib/coverage'
+import {
+  resolveSessionState,
+  sessionStateDotClass,
+  sessionStateLabel,
+} from '../lib/sessionState'
 import { countryDecal, formatGpDateRange } from '../lib/gpIdentity'
+import type { WeekendContext } from '../types'
 
 interface Props {
   currentMeetingKey?: number
   currentSessionKey?: number
+  context?: WeekendContext | null
+  now?: Date
   onClose: () => void
 }
 
-export function WeekendSwitcher({ currentMeetingKey, currentSessionKey, onClose }: Props) {
+export function WeekendSwitcher({
+  currentMeetingKey,
+  currentSessionKey,
+  context,
+  now: nowProp,
+  onClose,
+}: Props) {
   const navigate = useNavigate()
   const seasonsQuery = useQuery({ queryKey: ['seasons'], queryFn: fetchSeasons })
   const [year, setYear] = useState<number | null>(null)
   const [openMeetingKey, setOpenMeetingKey] = useState<number | null>(
     currentMeetingKey ?? null,
   )
-
+  const now = nowProp ?? new Date()
-  useEffect(() => {
-    if (year == null && seasonsQuery.data?.length) {
-      setYear(seasonsQuery.data[0])
-    }
-  }, [seasonsQuery.data, year])
-
-  const meetingsQuery = useQuery({
-    queryKey: ['meetings', year],
-    queryFn: () => fetchLocalMeetings(year!),
-    enabled: year != null,
-  })
 
   const weekendQuery = useQuery({
     queryKey: ['weekend', openMeetingKey],
@@ -37,6 +40,22 @@ export function WeekendSwitcher({ currentMeetingKey, currentSessionKey, onClose
     enabled: openMeetingKey != null,
   })
 
+  useEffect(() => {
+    if (year != null) return
+    const currentYear = weekendQuery.data?.meeting?.year
+    if (currentYear) {
+      setYear(currentYear)
+    } else if (seasonsQuery.data?.length) {
+      setYear(seasonsQuery.data[0])
+    }
+  }, [seasonsQuery.data, weekendQuery.data, year])
+
+  const meetingsQuery = useQuery({
+    queryKey: ['meetings', year],
+    queryFn: () => fetchLocalMeetings(year!),
+    enabled: year != null,
+  })
+
   const seasons = seasonsQuery.data ?? []
   const meetings = meetingsQuery.data ?? []
   const weekend = weekendQuery.data
@@ -106,9 +125,16 @@ export function WeekendSwitcher({ currentMeetingKey, currentSessionKey, onClose
                     {weekendQuery.isLoading && (
                       <div className="rh-switcher-empty">loading sessions…</div>
                     )}
-                    {weekend && weekend.meeting_key === m.meeting_key &&
+                    {weekend &&
-                      weekend.sessions.map(({ session, source, datasets }) => {
+                      weekend.meeting_key === m.meeting_key &&
+                      weekend.sessions.map((weekendSession) => {
+                        const { session } = weekendSession
                         const active = session.session_key === currentSessionKey
+                        const state = resolveSessionState({
+                          weekendSession,
+                          context,
+                          now,
+                        })
                         return (
                           <button
                             key={session.session_key}
@@ -122,8 +148,11 @@ export function WeekendSwitcher({ currentMeetingKey, currentSessionKey, onClose
                             </span>
                             <span className="rh-switcher-sess-name">{session.session_name}</span>
                             <span className="rh-switcher-sess-cov mono">
-                              <span className={`cc-cov-dot cc-cov-${source}`} aria-hidden="true" />
+                              <span
-                              {formatCoverageHint(datasets)}
+                                className={`cc-cov-dot ${sessionStateDotClass(state)}`}
+                                aria-hidden="true"
+                              />
+                              {sessionStateLabel(state)}
                             </span>
                           </button>
                         )

frontend/src/components/weekend/BetweenRacesView.tsx

@@ -0,0 +1,152 @@
+import { Link } from '@tanstack/react-router'
+import { ChevronRight, Flag as FlagIcon } from 'lucide-react'
+import type {
+  WeekendBriefingItem,
+  WeekendChampionshipImpact,
+  WeekendContext,
+  WeekendViewState,
+} from '../../types'
+import {
+  BriefingStrip,
+  ChampionshipImpactCard,
+  ChampionshipRoundStrip,
+  CountdownDisplay,
+  EventPodium,
+  Flag,
+} from './shared'
+import { analysisSessionKey, meetingIdentity } from '../../lib/weekendContext'
+import { parseScheduleTime } from '../../lib/schedule'
+
+const EYEBROW: Record<string, string> = {
+  between_weekends: 'Between races',
+  post_weekend: 'Post-weekend',
+  season_complete: 'Season complete',
+}
+
+function formatSessionLine(name: string | undefined, start: string | undefined): string {
+  if (!name) return 'Schedule to be confirmed'
+  const date = start ? parseScheduleTime(start) : null
+  if (!date) return name
+  const when = date.toLocaleString('en-GB', {
+    weekday: 'long',
+    hour: '2-digit',
+    minute: '2-digit',
+    hour12: false,
+  })
+  return `${name} · ${when}`
+}
+
+export function BetweenRacesView({
+  context,
+  now,
+  view,
+  championship,
+  briefing,
+}: {
+  context: WeekendContext
+  now: Date
+  view: WeekendViewState
+  championship?: WeekendChampionshipImpact
+  briefing: WeekendBriefingItem[]
+}) {
+  const eyebrow = EYEBROW[view] ?? 'Between races'
+
+  const previous = context.previous_completed_session
+  const previousMeeting = meetingIdentity(previous?.meeting ?? context.previous_meeting)
+  const nextMeeting = meetingIdentity(context.next_meeting)
+  const nextSession = context.next_session?.session
+  const analysisKey = analysisSessionKey(context)
+
+  return (
+    <div className="wk-between" data-testid="weekend-between-races" data-state={view}>
+      <div className="wk-eyebrow mono" data-testid="wk-eyebrow">{eyebrow}</div>
+
+      <div className="wk-top-grid">
+        {previousMeeting && (
+          <section className="wk-event-card wk-event-last" data-testid="wk-last-event">
+            <header className="wk-event-head">
+              <div className="wk-event-id">
+                <Flag code={previousMeeting.country_code} flag={previousMeeting.country_flag} />
+                <h2 className="wk-event-name">{previousMeeting.meeting_name}</h2>
+              </div>
+              <span className="wk-event-tag wk-tag-done mono">
+                <FlagIcon size={13} aria-hidden="true" /> Completed
+              </span>
+            </header>
+            <div className="wk-event-body">
+              <EventPodium sessionKey={analysisKey} />
+              <div className="wk-story-card">
+                <span className="wk-story-label">What decided it?</span>
+                {analysisKey ? (
+                  <Link
+                    to="/race-hub"
+                    search={{ session_key: analysisKey }}
+                    className="wk-cta wk-cta-primary"
+                    data-testid="wk-explore-race-story"
+                  >
+                    Explore Race Story <ChevronRight size={15} aria-hidden="true" />
+                  </Link>
+                ) : (
+                  <p className="wk-story-text" data-testid="wk-no-analysis">
+                    Analysis for this session is not available locally yet.
+                  </p>
+                )}
+              </div>
+            </div>
+          </section>
+        )}
+
+        {nextMeeting ? (
+          <section className="wk-event-card wk-event-next" data-testid="wk-next-event">
+            <header className="wk-event-head">
+              <div className="wk-event-id">
+                <Flag code={nextMeeting.country_code} flag={nextMeeting.country_flag} />
+                <h2 className="wk-event-name">{nextMeeting.meeting_name}</h2>
+              </div>
+              <span className="wk-event-tag wk-tag-next mono">Next event</span>
+            </header>
+            <div className="wk-next-body">
+              <CountdownDisplay target={nextSession?.date_start ?? nextMeeting.date_start} now={now} />
+              <div className="wk-next-session">
+                <span className="wk-next-label mono">Next session</span>
+                <span className="wk-next-value">
+                  {formatSessionLine(nextSession?.session_name, nextSession?.date_start)}
+                </span>
+              </div>
+              <Link to="/preview" className="wk-cta wk-cta-primary wk-cta-wide" data-testid="wk-prepare">
+                Prepare for {nextMeeting.short_name}
+                <ChevronRight size={15} aria-hidden="true" />
+              </Link>
+            </div>
+          </section>
+        ) : (
+          <section className="wk-event-card wk-event-next" data-testid="wk-season-complete-card">
+            <header className="wk-event-head">
+              <h2 className="wk-event-name">That&apos;s a wrap</h2>
+              <span className="wk-event-tag wk-tag-next mono">Off-season</span>
+            </header>
+            <div className="wk-next-body">
+              <p className="wk-season-complete-copy">
+                The {context.season} calendar is complete. Explore the season&apos;s races or revisit the championship
+                battle while the next schedule is confirmed.
+              </p>
+              <Link to="/explore" className="wk-cta wk-cta-primary wk-cta-wide" data-testid="wk-season-complete-explore">
+                Explore the season <ChevronRight size={15} aria-hidden="true" />
+              </Link>
+            </div>
+          </section>
+        )}
+      </div>
+
+      <div className="wk-mid-grid">
+        {championship && <ChampionshipImpactCard impact={championship} />}
+        <ChampionshipRoundStrip
+          round={context.championship_round}
+          total={context.total_championship_rounds}
+        />
+      </div>
+
+      {briefing.length > 0 && <BriefingStrip items={briefing} />}
+    </div>
+  )
+}

frontend/src/components/weekend/BetweenSessionsView.tsx

@@ -0,0 +1,83 @@
+import { Link } from '@tanstack/react-router'
+import { ChevronRight } from 'lucide-react'
+import type { WeekendBriefingItem, WeekendContext, WeekendViewState } from '../../types'
+import { BriefingStrip, CountdownDisplay, EventPodium, SessionRail, railNodes } from './shared'
+import { analysisSessionKey, meetingIdentity } from '../../lib/weekendContext'
+import { parseScheduleTime } from '../../lib/schedule'
+
+function nextSessionWhen(start: string | undefined): string {
+  const date = start ? parseScheduleTime(start) : null
+  if (!date) return 'Time to be confirmed'
+  return date.toLocaleString('en-GB', {
+    weekday: 'short',
+    hour: '2-digit',
+    minute: '2-digit',
+    hour12: false,
+  })
+}
+
+export function BetweenSessionsView({
+  context,
+  now,
+  view,
+  briefing,
+}: {
+  context: WeekendContext
+  now: Date
+  view: WeekendViewState
+  briefing: WeekendBriefingItem[]
+}) {
+  const settling = view === 'session_settling'
+  const focus = meetingIdentity(context.focus_meeting)
+  const previous = context.previous_completed_session
+  const previousName = previous?.session.session_name ?? 'Last session'
+  const next = context.next_session?.session
+  const analysisKey = analysisSessionKey(context)
+  const nodes = railNodes(previous, context.active_session, context.next_session)
+
+  return (
+    <div className="wk-sessions" data-testid="weekend-between-sessions" data-state={view}>
+      <div className="wk-eyebrow mono" data-testid="wk-eyebrow">
+        {settling ? 'Session settling' : 'Between sessions'}
+      </div>
+
+      <header className="wk-sessions-head">
+        <h1 className="wk-sessions-title">{focus?.meeting_name ?? 'Race weekend'}</h1>
+        {focus?.circuit_short_name && <p className="wk-sessions-circuit mono">{focus.circuit_short_name}</p>}
+      </header>
+
+      <SessionRail nodes={nodes} />
+
+      {previous && (
+        <section className="wk-recap-card" data-testid="wk-last-session">
+          <span className="wk-recap-eyebrow mono">
+            {previousName} · {settling ? 'Settling' : 'Complete'}
+          </span>
+          <h2 className="wk-recap-title">What happened in {previousName}</h2>
+          <EventPodium sessionKey={analysisKey} />
+        </section>
+      )}
+
+      {next && (
+        <section className="wk-upnext-card" data-testid="wk-next-session">
+          <span className="wk-upnext-eyebrow mono">Up next</span>
+          <h2 className="wk-upnext-title">{next.session_name}</h2>
+          <CountdownDisplay target={next.date_start} now={now} compact />
+          <p className="wk-upnext-when mono">{nextSessionWhen(next.date_start)}</p>
+          {analysisKey && (
+            <Link
+              to="/race-hub"
+              search={{ session_key: analysisKey }}
+              className="wk-cta wk-cta-primary wk-cta-wide"
+              data-testid="wk-view-recap"
+            >
+              View {previousName} recap <ChevronRight size={15} aria-hidden="true" />
+            </Link>
+          )}
+        </section>
+      )}
+
+      {briefing.length > 0 && <BriefingStrip items={briefing} />}
+    </div>
+  )
+}

frontend/src/components/weekend/LiveHandoffView.tsx

@@ -0,0 +1,47 @@
+import { Link } from '@tanstack/react-router'
+import { ChevronRight, Radio } from 'lucide-react'
+import type { WeekendContext } from '../../types'
+import { EventPodium, Flag, SessionRail, railNodes } from './shared'
+import { analysisSessionKey, meetingIdentity } from '../../lib/weekendContext'
+
+export function LiveHandoffView({ context }: { context: WeekendContext }) {
+  const focus = meetingIdentity(context.focus_meeting ?? context.active_session?.meeting)
+  const active = context.active_session?.session
+  const previous = context.previous_completed_session
+  const previousName = previous?.session.session_name ?? 'Last session'
+  const analysisKey = analysisSessionKey(context)
+  const nodes = railNodes(previous, context.active_session, context.next_session)
+
+  return (
+    <div className="wk-live" data-testid="weekend-live" data-state="session_live">
+      <div className="wk-eyebrow mono" data-testid="wk-eyebrow">Session live</div>
+
+      <section className="wk-live-card" data-testid="wk-live-card">
+        <div className="wk-live-head">
+          <div className="wk-event-id">
+            <Flag code={focus?.country_code} flag={focus?.country_flag} />
+            <h1 className="wk-sessions-title">{focus?.meeting_name ?? 'Live session'}</h1>
+          </div>
+          <span className="wk-live-pulse" aria-hidden="true" />
+        </div>
+        {focus?.circuit_short_name && <p className="wk-sessions-circuit mono">{focus.circuit_short_name}</p>}
+        <p className="wk-live-lead">
+          {active?.session_name ? `${active.session_name} is on track now.` : 'A session is running now.'}
+        </p>
+        <Link to="/live" className="wk-cta wk-cta-primary wk-cta-wide" data-testid="wk-watch-live">
+          <Radio size={15} aria-hidden="true" /> Watch live timing <ChevronRight size={15} aria-hidden="true" />
+        </Link>
+      </section>
+
+      <SessionRail nodes={nodes} />
+
+      {previous && (
+        <section className="wk-recap-card" data-testid="wk-last-session">
+          <span className="wk-recap-eyebrow mono">{previousName} · Complete</span>
+          <h2 className="wk-recap-title">What happened in {previousName}</h2>
+          <EventPodium sessionKey={analysisKey} />
+        </section>
+      )}
+    </div>
+  )
+}

frontend/src/components/weekend/PreSessionView.tsx

@@ -0,0 +1,56 @@
+import { Link } from '@tanstack/react-router'
+import { ChevronRight } from 'lucide-react'
+import type { WeekendContext } from '../../types'
+import { RacePreviewPage } from '../../pages/RacePreviewPage'
+import { ChampionshipRoundStrip, CountdownDisplay, Flag, SessionRail, railNodes } from './shared'
+import { meetingIdentity } from '../../lib/weekendContext'
+
+/**
+ * PreSessionView folds the race preview surface into the Weekend home so there is
+ * no separate Preview destination. It reuses the existing preview page content and
+ * frames it with the next-session countdown and compact season navigation. It also
+ * backs the /preview alias, so saved preview links resolve here instead of looping.
+ */
+export function PreSessionView({ context, now }: { context: WeekendContext; now: Date }) {
+  const meeting = meetingIdentity(context.next_meeting ?? context.focus_meeting)
+  const next = context.next_session?.session
+  const nextStart = next?.date_start ?? meeting?.date_start
+  const nodes = railNodes(
+    context.previous_completed_session,
+    context.active_session,
+    context.next_session,
+  )
+
+  return (
+    <div className="wk-pre" data-testid="weekend-pre-session" data-state="pre_session">
+      <div className="wk-eyebrow mono" data-testid="wk-eyebrow">Pre-session</div>
+
+      {meeting && (
+        <header className="wk-pre-head" data-testid="wk-pre-head">
+          <div className="wk-event-id">
+            <Flag code={meeting.country_code} flag={meeting.country_flag} />
+            <h1 className="wk-sessions-title">{meeting.meeting_name}</h1>
+          </div>
+          <div className="wk-pre-countdown">
+            <span className="wk-next-label mono">{next?.session_name ?? 'Next session'}</span>
+            <CountdownDisplay target={nextStart} now={now} />
+          </div>
+          <Link to="/live" className="wk-cta wk-cta-ghost" data-testid="wk-pre-live">
+            Live timing <ChevronRight size={14} aria-hidden="true" />
+          </Link>
+        </header>
+      )}
+
+      {nodes.length > 0 && <SessionRail nodes={nodes} />}
+
+      <div className="wk-pre-preview" data-testid="wk-pre-preview">
+        <RacePreviewPage />
+      </div>
+
+      <ChampionshipRoundStrip
+        round={context.championship_round}
+        total={context.total_championship_rounds}
+      />
+    </div>
+  )
+}

frontend/src/components/weekend/StatusViews.tsx

@@ -0,0 +1,36 @@
+import { Link } from '@tanstack/react-router'
+
+export function WeekendLoading() {
+  return (
+    <div className="wk-status wk-status-loading" data-testid="weekend-loading" aria-busy="true">
+      <span className="wk-status-eyebrow mono">box-box · weekend</span>
+      <p className="wk-status-title">Reading the weekend…</p>
+    </div>
+  )
+}
+
+export function WeekendError({ message }: { message?: string }) {
+  return (
+    <div className="wk-status wk-status-error" data-testid="weekend-error" role="alert">
+      <span className="wk-status-eyebrow mono">box-box · weekend</span>
+      <p className="wk-status-title">Weekend unavailable</p>
+      <p className="wk-status-sub">{message ?? 'Something went wrong loading the weekend context.'}</p>
+    </div>
+  )
+}
+
+export function WeekendLimited({ message, season }: { message?: string; season?: number }) {
+  return (
+    <div className="wk-status wk-status-limited" data-testid="weekend-limited">
+      <span className="wk-status-eyebrow mono">box-box · weekend</span>
+      <p className="wk-status-title">Nothing to show yet</p>
+      <p className="wk-status-sub">
+        {message ?? `No weekend data for the ${season || 'current'} season is available right now.`}
+      </p>
+      <div className="wk-status-actions">
+        <Link to="/live" className="wk-cta wk-cta-ghost">Live timing</Link>
+        <Link to="/explore" className="wk-cta wk-cta-ghost">Explore</Link>
+      </div>
+    </div>
+  )
+}

frontend/src/components/weekend/WeekendFocusBanner.tsx

@@ -0,0 +1,65 @@
+import { Link } from '@tanstack/react-router'
+import { useQuery } from '@tanstack/react-query'
+import { ChevronRight } from 'lucide-react'
+import { fetchWeekend } from '../../api'
+import { meetingIdentity } from '../../lib/weekendContext'
+
+/**
+ * Restores Race Hub → Weekend meeting/session context from the URL search
+ * contract. Deep-linkable and reload-safe — no hidden component memory.
+ */
+export function WeekendFocusBanner({
+  meetingKey,
+  sessionKey,
+}: {
+  meetingKey?: number
+  sessionKey?: number
+}) {
+  const hasFocus = (meetingKey != null && meetingKey > 0) || (sessionKey != null && sessionKey > 0)
+  const weekendQuery = useQuery({
+    queryKey: ['weekend', meetingKey],
+    queryFn: () => fetchWeekend(meetingKey!),
+    enabled: meetingKey != null && meetingKey > 0,
+    staleTime: 60_000,
+  })
+
+  if (!hasFocus) return null
+
+  const weekend = weekendQuery.data
+  const meeting = meetingIdentity(weekend?.meeting)
+  const session = weekend?.sessions.find((s) => s.session.session_key === sessionKey)?.session
+  const meetingLabel = meeting?.meeting_name ?? (meetingKey ? `Meeting ${meetingKey}` : 'Selected weekend')
+  const sessionLabel = session?.session_name ?? (sessionKey ? `Session ${sessionKey}` : null)
+
+  return (
+    <section
+      className="wk-focus"
+      data-testid="wk-focus-context"
+      data-meeting-key={meetingKey ?? undefined}
+      data-session-key={sessionKey ?? undefined}
+      aria-label="Selected weekend context"
+    >
+      <div className="wk-focus-copy">
+        <span className="wk-focus-eyebrow mono">From Race Hub</span>
+        <h2 className="wk-focus-title" data-testid="wk-focus-meeting">
+          {meetingLabel}
+        </h2>
+        {sessionLabel && (
+          <p className="wk-focus-session" data-testid="wk-focus-session">
+            Selected session · {sessionLabel}
+          </p>
+        )}
+      </div>
+      {sessionKey != null && sessionKey > 0 && (
+        <Link
+          to="/race-hub"
+          search={{ session_key: sessionKey }}
+          className="wk-cta wk-cta-primary wk-focus-cta"
+          data-testid="wk-return-analysis"
+        >
+          Continue analysis <ChevronRight size={15} aria-hidden="true" />
+        </Link>
+      )}
+    </section>
+  )
+}

frontend/src/components/weekend/shared.tsx

@@ -0,0 +1,277 @@
+import { useQuery } from '@tanstack/react-query'
+import { Link } from '@tanstack/react-router'
+import { fetchRaceHub } from '../../api'
+import { countryFlag } from '../../lib/gpIdentity'
+import { parseScheduleTime } from '../../lib/schedule'
+import { podiumFromResults } from '../../lib/weekendContext'
+import { teamColor } from '../../utils'
+import type {
+  ContextSession,
+  WeekendChampionshipImpact,
+  WeekendBriefingItem,
+  WeekendPodiumEntry,
+} from '../../types'
+
+export function Flag({ code, flag }: { code?: string; flag?: string }) {
+  const glyph = countryFlag({ country_code: code ?? '', country_flag: flag ?? '' })
+  if (!glyph) return null
+  return <span className="wk-flag" aria-hidden="true">{glyph}</span>
+}
+
+interface CountdownParts {
+  days: number
+  hours: number
+  minutes: number
+  seconds: number
+  reached: boolean
+}
+
+export function countdownParts(target: string | undefined, now: Date): CountdownParts | null {
+  const date = target ? parseScheduleTime(target) : null
+  if (!date) return null
+  const diff = date.getTime() - now.getTime()
+  const clamped = Math.max(0, diff)
+  const totalSeconds = Math.floor(clamped / 1000)
+  return {
+    days: Math.floor(totalSeconds / 86400),
+    hours: Math.floor((totalSeconds % 86400) / 3600),
+    minutes: Math.floor((totalSeconds % 3600) / 60),
+    seconds: totalSeconds % 60,
+    reached: diff <= 0,
+  }
+}
+
+export function CountdownDisplay({
+  target,
+  now,
+  compact,
+}: {
+  target: string | undefined
+  now: Date
+  compact?: boolean
+}) {
+  const parts = countdownParts(target, now)
+  if (!parts) {
+    return (
+      <span className="wk-countdown-tbc mono" data-testid="wk-countdown">
+        Schedule TBC
+      </span>
+    )
+  }
+  if (parts.reached) {
+    return <span className="wk-countdown-live" data-testid="wk-countdown">Starting now</span>
+  }
+  if (compact || parts.days === 0) {
+    const hh = String(parts.days * 24 + parts.hours).padStart(2, '0')
+    return (
+      <span className="wk-countdown-clock mono" data-testid="wk-countdown">
+        {hh}:{String(parts.minutes).padStart(2, '0')}:{String(parts.seconds).padStart(2, '0')}
+      </span>
+    )
+  }
+  return (
+    <span className="wk-countdown" data-testid="wk-countdown">
+      <span className="wk-count-unit"><b>{parts.days}</b>D</span>
+      <span className="wk-count-unit"><b>{String(parts.hours).padStart(2, '0')}</b>H</span>
+      <span className="wk-count-unit"><b>{String(parts.minutes).padStart(2, '0')}</b>M</span>
+    </span>
+  )
+}
+
+/**
+ * EventPodium fetches and renders the podium for a completed analysis session.
+ * When no analysable session key is available (e.g. an archived result with no
+ * local analysis), it renders an explicit empty state rather than fetching.
+ */
+export function EventPodium({ sessionKey }: { sessionKey?: number }) {
+  const enabled = typeof sessionKey === 'number' && sessionKey > 0
+  const query = useQuery({
+    queryKey: ['race-hub', sessionKey, 'podium'],
+    queryFn: () => fetchRaceHub(sessionKey as number),
+    enabled,
+    staleTime: 60_000,
+  })
+
+  const podium: WeekendPodiumEntry[] = podiumFromResults(query.data?.results ?? [])
+
+  if (!enabled) {
+    return (
+      <div className="wk-podium-empty" data-testid="wk-podium-empty">
+        Result not available yet.
+      </div>
+    )
+  }
+
+  if (podium.length === 0) {
+    return (
+      <div className="wk-podium-empty" data-testid="wk-podium-empty">
+        {query.isLoading ? 'Loading result…' : 'Result not available yet.'}
+      </div>
+    )
+  }
+
+  return (
+    <ol className="wk-podium" data-testid="wk-podium">
+      {podium.map((p) => (
+        <li key={p.driver_number} className="wk-podium-row" style={{ ['--wk-team' as string]: teamColor(p.team_colour) }}>
+          <span className="wk-podium-pos mono">{p.position}</span>
+          <span className="wk-podium-code">{p.name_acronym}</span>
+          <span className="wk-podium-gap mono">{p.gap}</span>
+        </li>
+      ))}
+    </ol>
+  )
+}
+
+export function ChampionshipImpactCard({ impact }: { impact: WeekendChampionshipImpact }) {
+  const leader = impact.leaders[0]
+  return (
+    <section className="wk-champ" data-testid="wk-champ-impact">
+      <header className="wk-card-head">
+        <span className="wk-card-title">Championship impact</span>
+        <Link to="/championship" className="wk-card-link">Standings →</Link>
+      </header>
+      <ol className="wk-champ-list">
+        {impact.leaders.map((d) => {
+          const gap = leader && d.position !== 1 ? leader.points - d.points : 0
+          return (
+            <li key={d.driver_number} className="wk-champ-row" style={{ ['--wk-team' as string]: teamColor(d.team_colour) }}>
+              <span className="wk-champ-pos mono">{d.position}</span>
+              <span className="wk-champ-code">{d.name_acronym}</span>
+              <span className="wk-champ-pts mono">{d.points}</span>
+              <span className="wk-champ-gap mono">{d.position === 1 ? '—' : `-${gap}`}</span>
+            </li>
+          )
+        })}
+      </ol>
+      {impact.note && <p className="wk-champ-note">{impact.note}</p>}
+    </section>
+  )
+}
+
+export function BriefingStrip({ items }: { items: WeekendBriefingItem[] }) {
+  if (items.length === 0) return null
+  return (
+    <section className="wk-briefing" data-testid="wk-briefing">
+      <header className="wk-card-head">
+        <span className="wk-card-title">Since the chequered flag</span>
+        <Link to="/briefing" className="wk-card-link">All briefing →</Link>
+      </header>
+      <ul className="wk-briefing-list">
+        {items.map((item) => (
+          <li key={item.url} className="wk-briefing-item">
+            <a href={item.url} target="_blank" rel="noreferrer" className="wk-briefing-link">
+              {item.category && <span className="wk-briefing-cat mono">{item.category}</span>}
+              <span className="wk-briefing-title">{item.title}</span>
+              <span className="wk-briefing-source mono">{item.source}</span>
+            </a>
+          </li>
+        ))}
+      </ul>
+    </section>
+  )
+}
+
+/**
+ * ChampionshipRoundStrip is a compact, progressively-disclosed round indicator.
+ * The canonical contract exposes only the current round and total, so the strip
+ * shows "Round N of M" and links out to Explore for the full calendar rather than
+ * reintroducing the whole calendar on the Weekend home.
+ */
+export function ChampionshipRoundStrip({ round, total }: { round: number; total: number }) {
+  if (round <= 0 || total <= 0) return null
+  const pct = Math.min(100, Math.round((round / total) * 100))
+  return (
+    <section className="wk-season-nav" data-testid="wk-season-nav" aria-label="Season progress">
+      <div className="wk-season-progress">
+        <div className="wk-season-progress-head">
+          <span className="wk-card-title">Season progress</span>
+          <Link to="/explore" className="wk-card-link" data-testid="wk-season-explore">
+            Full calendar →
+          </Link>
+        </div>
+        <div
+          className="wk-season-bar"
+          role="progressbar"
+          aria-valuenow={round}
+          aria-valuemin={1}
+          aria-valuemax={total}
+          aria-label={`Round ${round} of ${total}`}
+        >
+          <span className="wk-season-bar-fill" style={{ width: `${pct}%` }} aria-hidden="true" />
+        </div>
+        <p className="wk-season-progress-label mono">
+          Round {round} of {total}
+        </p>
+      </div>
+    </section>
+  )
+}
+
+interface TimelineNode {
+  key: string
+  session_name: string
+  status: 'done' | 'live' | 'next'
+}
+
+/**
+ * SessionRail renders the previous/active/next sessions the canonical context
+ * exposes as a compact three-node rail. It is intentionally derived only from the
+ * canonical refs — the contract does not enumerate a full weekend session list.
+ */
+export function SessionRail({ nodes }: { nodes: TimelineNode[] }) {
+  if (nodes.length === 0) return null
+  return (
+    <ol className="wk-timeline" data-testid="wk-timeline" role="list">
+      {nodes.map((n) => (
+        <li key={n.key} className={`wk-timeline-node wk-timeline-${n.status}`} role="listitem">
+          <span className="wk-timeline-dot" aria-hidden="true" />
+          <span className="wk-timeline-name">{shortSessionName(n.session_name)}</span>
+          <span className="wk-timeline-state mono">{stateLabel(n.status)}</span>
+        </li>
+      ))}
+    </ol>
+  )
+}
+
+/** Build the compact session rail from the canonical previous/active/next refs. */
+export function railNodes(
+  previous: ContextSession | undefined,
+  active: ContextSession | undefined,
+  next: ContextSession | undefined,
+): TimelineNode[] {
+  const nodes: TimelineNode[] = []
+  if (previous?.session.session_name) {
+    nodes.push({ key: `prev-${previous.session.session_key}`, session_name: previous.session.session_name, status: 'done' })
+  }
+  if (active?.session.session_name) {
+    nodes.push({ key: `live-${active.session.session_key}`, session_name: active.session.session_name, status: 'live' })
+  }
+  if (next?.session.session_name) {
+    nodes.push({ key: `next-${next.session.session_key}`, session_name: next.session.session_name, status: 'next' })
+  }
+  return nodes
+}
+
+function shortSessionName(name: string): string {
+  const map: Record<string, string> = {
+    'Practice 1': 'FP1',
+    'Practice 2': 'FP2',
+    'Practice 3': 'FP3',
+    Qualifying: 'Quali',
+    'Sprint Qualifying': 'SQ',
+    'Sprint Shootout': 'SQ',
+  }
+  return map[name] ?? name
+}
+
+function stateLabel(status: TimelineNode['status']): string {
+  switch (status) {
+    case 'done':
+      return 'Complete'
+    case 'live':
+      return 'Live'
+    default:
+      return 'Next'
+  }
+}

frontend/src/hooks/useWeekendContext.ts

@@ -0,0 +1,89 @@
+import { useEffect, useMemo, useState } from 'react'
+import { useQuery } from '@tanstack/react-query'
+import { fetchChampionshipHub, fetchNews, fetchWeekendContext } from '../api'
+import { championshipImpact, briefingItems } from '../lib/weekendContext'
+import type {
+  WeekendChampionshipImpact,
+  WeekendBriefingItem,
+  WeekendContext,
+} from '../types'
+
+export type WeekendLoadState = 'loading' | 'error' | 'ready'
+
+export interface UseWeekendContextResult {
+  /** Canonical context, present only when loadState === 'ready'. */
+  context: WeekendContext | null
+  loadState: WeekendLoadState
+  error?: Error
+  /** Supplementary championship movers (not part of the #72 contract). */
+  championship?: WeekendChampionshipImpact
+  /** Supplementary briefing items (not part of the #72 contract). */
+  briefing: WeekendBriefingItem[]
+  now: Date
+}
+
+/**
+ * useWeekendContext reads the canonical /api/v1/weekend-context endpoint as the
+ * single source of truth for the Weekend home. When the canonical read succeeds
+ * it layers on two pieces of supplementary data that the contract intentionally
+ * omits — championship movers and the paddock briefing — and nothing else.
+ *
+ * It deliberately does NOT fan out to season / meetings / per-weekend / OpenF1
+ * session / live-state queries: those would defeat the local-first canonical read
+ * model and can hit the rate-limited OpenF1 REST surface during active sessions.
+ * Supplementary queries are gated on a successful canonical read so a failing or
+ * pending endpoint issues no extra requests.
+ */
+export function useWeekendContext(): UseWeekendContextResult {
+  const [now, setNow] = useState(() => Date.now())
+  useEffect(() => {
+    const timer = window.setInterval(() => setNow(Date.now()), 1000)
+    return () => window.clearInterval(timer)
+  }, [])
+  const nowDate = useMemo(() => new Date(now), [now])
+
+  const contextQuery = useQuery({
+    queryKey: ['weekend-context'],
+    queryFn: fetchWeekendContext,
+    staleTime: 30_000,
+  })
+
+  const canonical = contextQuery.data ?? null
+  const canonicalReady = canonical != null
+  const season = canonical?.season
+
+  // Supplementary data — only fetched once the canonical context has resolved,
+  // so a pending/failed canonical read never triggers a request fan-out.
+  const championshipQuery = useQuery({
+    queryKey: ['championship-hub', season ?? 'current'],
+    queryFn: () => fetchChampionshipHub(season),
+    enabled: canonicalReady,
+    staleTime: 60_000,
+  })
+
+  const newsQuery = useQuery({
+    queryKey: ['news', 6],
+    queryFn: () => fetchNews(6),
+    enabled: canonicalReady,
+    staleTime: 60_000,
+  })
+
+  const championship = useMemo(
+    () => championshipImpact(championshipQuery.data),
+    [championshipQuery.data],
+  )
+  const briefing = useMemo(() => briefingItems(newsQuery.data ?? []), [newsQuery.data])
+
+  let loadState: WeekendLoadState = 'loading'
+  if (contextQuery.isError) loadState = 'error'
+  else if (canonicalReady) loadState = 'ready'
+
+  return {
+    context: canonical,
+    loadState,
+    error: contextQuery.error instanceof Error ? contextQuery.error : undefined,
+    championship,
+    briefing,
+    now: nowDate,
+  }
+}

frontend/src/lib/chapters.ts

@@ -0,0 +1,132 @@
+import type { Chapter } from '../types'
+
+export function chapterKindLabel(kind: string): string {
+  switch (kind) {
+    case 'start':
+      return 'GO'
+    case 'safety_car':
+      return 'SC'
+    case 'virtual_safety_car':
+      return 'VSC'
+    case 'red_flag':
+      return 'RF'
+    case 'pit_phase':
+      return 'PIT'
+    case 'decisive_swing':
+      return '▲'
+    case 'finish':
+      return 'FIN'
+    default:
+      return kind.slice(0, 3).toUpperCase()
+  }
+}
+
+export function chapterLapRange(chapter: Chapter): string {
+  if (chapter.start_lap === chapter.end_lap) {
+    return `L${chapter.start_lap}`
+  }
+  return `L${chapter.start_lap}–L${chapter.end_lap}`
+}
+
+/** Normalized scrub position (0–1) for a chapter's start time on the chart axis. */
+export function chapterStartScrub(
+  chapter: Chapter,
+  tMin: number,
+  tRange: number,
+): number | null {
+  if (!chapter.start_time || tRange <= 0) return null
+  const ms = new Date(chapter.start_time).getTime()
+  if (Number.isNaN(ms)) return null
+  return Math.max(0, Math.min(1, (ms - tMin) / tRange))
+}
+
+/** Normalized scrub position (0–1) for a chapter's end time on the chart axis. */
+export function chapterEndScrub(
+  chapter: Chapter,
+  tMin: number,
+  tRange: number,
+): number | null {
+  const raw = chapter.end_time ?? chapter.start_time
+  if (!raw || tRange <= 0) return null
+  const ms = new Date(raw).getTime()
+  if (Number.isNaN(ms)) return null
+  return Math.max(0, Math.min(1, (ms - tMin) / tRange))
+}
+
+/** Index of the chapter containing the current scrub position, if any.
+ * Uses the same 0–1 clamped bounds as chapterStartScrub/chapterEndScrub so
+ * chapters whose timestamps fall outside the position-sample window still
+ * activate when the scrubber is parked at the clamped edge. */
+export function activeChapterIndex(
+  chapters: Chapter[],
+  scrubTime: number | null,
+  tMin: number,
+  tRange: number,
+): number | null {
+  if (scrubTime === null || chapters.length === 0 || tRange <= 0) return null
+  for (let i = 0; i < chapters.length; i++) {
+    const start = chapterStartScrub(chapters[i], tMin, tRange)
+    const end = chapterEndScrub(chapters[i], tMin, tRange)
+    if (start === null || end === null) continue
+    const lo = Math.min(start, end)
+    const hi = Math.max(start, end)
+    if (scrubTime >= lo && scrubTime <= hi) return i
+  }
+  return null
+}
+
+/** Duration in ms each chapter should play during a ~90s tour. */
+export function chapterTourDurations(chapters: Chapter[], totalMs = 90_000): number[] {
+  if (chapters.length === 0) return []
+  const perChapter = totalMs / chapters.length
+  return chapters.map(() => perChapter)
+}
+
+/** Decimated position axis labels, e.g. P1, P5, P10, P15, P20. */
+export function decimatedPositionLabels(maxPos: number): number[] {
+  if (maxPos <= 1) return [1]
+  const labels = new Set<number>([1])
+  for (let pos = 5; pos < maxPos; pos += 5) {
+    labels.add(pos)
+  }
+  labels.add(maxPos)
+  return [...labels].sort((a, b) => a - b)
+}
+
+/** Subtle background fill for chapter time-bands on the position graph. */
+export function chapterBandFill(kind: string): string {
+  switch (kind) {
+    case 'safety_car':
+      return 'rgba(255, 153, 0, 0.14)'
+    case 'virtual_safety_car':
+      return 'rgba(255, 204, 0, 0.12)'
+    case 'red_flag':
+      return 'rgba(230, 36, 41, 0.12)'
+    case 'pit_phase':
+      return 'rgba(96, 165, 250, 0.08)'
+    case 'decisive_swing':
+      return 'rgba(34, 197, 94, 0.08)'
+    case 'finish':
+      return 'rgba(255, 204, 0, 0.06)'
+    default:
+      return 'rgba(255, 255, 255, 0.03)'
+  }
+}
+
+/** Minimum vertical spacing between colliding labels (SVG units). */
+export function deCollideYPositions(
+  items: ReadonlyArray<{ key: string | number; y: number }>,
+  minGap = 12,
+): Map<string | number, number> {
+  if (items.length === 0) return new Map()
+  const sorted = [...items].sort((a, b) => a.y - b.y)
+  const adjusted = sorted.map((item) => ({ ...item }))
+  for (let i = 1; i < adjusted.length; i++) {
+    const prev = adjusted[i - 1]
+    const curr = adjusted[i]
+    if (curr.y - prev.y < minGap) {
+      curr.y = prev.y + minGap
+    }
+  }
+  return new Map(adjusted.map((item) => [item.key, item.y]))
+}

frontend/src/lib/digest.ts

@@ -0,0 +1,293 @@
+import { meetingEndTime, meetingStartTime, mostRecentPastMeeting, nextUpcomingMeeting } from './schedule'
+import type { ChampHubDriver, ChampHubTeam, Meeting, NewsItem } from '../types'
+
+export interface GPWindow {
+  meeting_key: number
+  meeting_name: string
+  /** Inclusive lower bound: end of previous GP, or open for season opener. */
+  start: Date | null
+  /** Exclusive upper bound: start of next GP, or open after the final round. */
+  end: Date | null
+}
+
+export interface DigestTag {
+  kind: 'driver' | 'team'
+  key: string
+  label: string
+  colour: string
+}
+
+export type TaggedNewsItem = NewsItem & { tags: DigestTag[] }
+
+export const RECENT_BUCKET_KEY = '__recent__'
+
+interface MatchCandidate {
+  start: number
+  end: number
+  tag: DigestTag
+}
+
+interface TagPattern {
+  pattern: string
+  tag: DigestTag
+}
+
+function sortMeetings(meetings: Meeting[]): Meeting[] {
+  return [...meetings].sort((a, b) => {
+    const left = meetingStartTime(a)?.getTime() ?? 0
+    const right = meetingStartTime(b)?.getTime() ?? 0
+    if (left !== right) return left - right
+    return a.meeting_name.localeCompare(b.meeting_name)
+  })
+}
+
+/** Derive inter-race windows [prev GP end → next GP start] for each round. */
+export function gpWindows(meetings: Meeting[], _now: Date): GPWindow[] {
+  const sorted = sortMeetings(meetings)
+  return sorted.map((meeting, index) => ({
+    meeting_key: meeting.meeting_key,
+    meeting_name: meeting.meeting_name,
+    start: index > 0 ? meetingEndTime(sorted[index - 1]) : null,
+    end: index < sorted.length - 1 ? meetingStartTime(sorted[index + 1]) : null,
+  }))
+}
+
+function itemPublishedAt(item: NewsItem): Date | null {
+  if (!item.published_at) return null
+  const parsed = Date.parse(item.published_at)
+  return Number.isNaN(parsed) ? null : new Date(parsed)
+}
+
+function itemInWindow(published: Date, window: GPWindow): boolean {
+  if (window.start && published < window.start) return false
+  if (window.end && published >= window.end) return false
+  return true
+}
+
+export function windowForDate(windows: GPWindow[], published: Date): GPWindow | null {
+  const matches = windows.filter((window) => itemInWindow(published, window))
+  if (matches.length === 0) return null
+  return matches.reduce((best, window) => {
+    const bestStart = best.start?.getTime() ?? Number.NEGATIVE_INFINITY
+    const windowStart = window.start?.getTime() ?? Number.NEGATIVE_INFINITY
+    return windowStart >= bestStart ? window : best
+  })
+}
+
+export interface GroupedDigest {
+  windows: Array<{ window: GPWindow; items: NewsItem[] }>
+  recent: NewsItem[]
+}
+
+/** Bucket news items into GP windows; undated items land in `recent`. */
+export function groupByWindow(items: NewsItem[], windows: GPWindow[]): GroupedDigest {
+  const buckets = new Map<number, NewsItem[]>()
+  const recent: NewsItem[] = []
+
+  for (const item of items) {
+    const published = itemPublishedAt(item)
+    if (!published) {
+      recent.push(item)
+      continue
+    }
+    const match = windowForDate(windows, published)
+    if (!match) {
+      recent.push(item)
+      continue
+    }
+    const list = buckets.get(match.meeting_key) ?? []
+    list.push(item)
+    buckets.set(match.meeting_key, list)
+  }
+
+  const grouped = windows
+    .map((window) => ({
+      window,
+      items: buckets.get(window.meeting_key) ?? [],
+    }))
+    .filter((entry) => entry.items.length > 0)
+
+  return { windows: grouped, recent }
+}
+
+function driverLastName(fullName: string): string | null {
+  const parts = fullName.trim().split(/\s+/).filter(Boolean)
+  if (parts.length < 2) return null
+  return parts[parts.length - 1] ?? null
+}
+
+function buildTagPatterns(drivers: ChampHubDriver[], teams: ChampHubTeam[]): TagPattern[] {
+  const patterns: TagPattern[] = []
+
+  for (const team of teams) {
+    if (!team.team_name.trim()) continue
+    patterns.push({
+      pattern: team.team_name.toLowerCase(),
+      tag: {
+        kind: 'team',
+        key: `team:${team.team_name}`,
+        label: team.team_name,
+        colour: team.team_colour,
+      },
+    })
+  }
+
+  for (const driver of drivers) {
+    const colour = driver.team_colour
+    const base = {
+      kind: 'driver' as const,
+      colour,
+    }
+    if (driver.full_name.trim()) {
+      patterns.push({
+        pattern: driver.full_name.toLowerCase(),
+        tag: {
+          ...base,
+          key: `driver:${driver.name_acronym}`,
+          label: driver.name_acronym,
+        },
+      })
+      const lastName = driverLastName(driver.full_name)
+      if (lastName) {
+        patterns.push({
+          pattern: lastName.toLowerCase(),
+          tag: {
+            ...base,
+            key: `driver:${driver.name_acronym}`,
+            label: driver.name_acronym,
+          },
+        })
+      }
+    }
+    if (driver.name_acronym.trim()) {
+      patterns.push({
+        pattern: driver.name_acronym.toLowerCase(),
+        tag: {
+          ...base,
+          key: `driver:${driver.name_acronym}`,
+          label: driver.name_acronym,
+        },
+      })
+    }
+  }
+
+  patterns.sort((a, b) => b.pattern.length - a.pattern.length)
+  return patterns
+}
+
+function overlaps(a: MatchCandidate, b: MatchCandidate): boolean {
+  return a.start < b.end && b.start < a.end
+}
+
+/**
+ * Tag items via case-insensitive substring match on title + summary.
+ * Longest pattern wins on overlapping spans (v1 string match — no NLP).
+ *
+ * Known limitations: common-word last names, team names inside other words,
+ * and driver TLAs that appear in unrelated acronyms can false-positive.
+ */
+export function tagItems(
+  items: NewsItem[],
+  drivers: ChampHubDriver[],
+  teams: ChampHubTeam[],
+): TaggedNewsItem[] {
+  const patterns = buildTagPatterns(drivers, teams)
+
+  return items.map((item) => {
+    const haystack = `${item.title} ${item.summary ?? ''}`.toLowerCase()
+    const accepted: MatchCandidate[] = []
+
+    for (const { pattern, tag } of patterns) {
+      if (!pattern) continue
+      let from = 0
+      while (from <= haystack.length - pattern.length) {
+        const index = haystack.indexOf(pattern, from)
+        if (index === -1) break
+        const candidate: MatchCandidate = {
+          start: index,
+          end: index + pattern.length,
+          tag,
+        }
+        if (!accepted.some((match) => overlaps(match, candidate))) {
+          accepted.push(candidate)
+        }
+        from = index + 1
+      }
+    }
+
+    const tagsByKey = new Map<string, DigestTag>()
+    for (const match of accepted) {
+      tagsByKey.set(match.tag.key, match.tag)
+    }
+
+    return {
+      ...item,
+      tags: [...tagsByKey.values()].sort((a, b) => a.label.localeCompare(b.label)),
+    }
+  })
+}
+
+export function activeDigestWindow(
+  windows: GPWindow[],
+  meetings: Meeting[],
+  now: Date,
+): GPWindow | null {
+  const next = nextUpcomingMeeting(meetings, now)
+  if (next) {
+    return windows.find((window) => window.meeting_key === next.meeting_key) ?? null
+  }
+  const recent = mostRecentPastMeeting(meetings, now)
+  if (recent) {
+    return windows.find((window) => window.meeting_key === recent.meeting_key) ?? null
+  }
+  return windows[0] ?? null
+}
+
+export function sinceLastLabel(meetings: Meeting[], now: Date): string {
+  const last = mostRecentPastMeeting(meetings, now)
+  if (last) return last.meeting_name
+  const next = nextUpcomingMeeting(meetings, now)
+  if (next) return `Before ${next.meeting_name}`
+  return 'Pre-season'
+}
+
+export function itemsForWindow(items: TaggedNewsItem[], window: GPWindow | null): TaggedNewsItem[] {
+  if (!window) return []
+  return items.filter((item) => {
+    const published = itemPublishedAt(item)
+    return published != null && itemInWindow(published, window)
+  })
+}
+
+export function topTags(items: TaggedNewsItem[], limit = 5): DigestTag[] {
+  const counts = new Map<string, { tag: DigestTag; count: number }>()
+  for (const item of items) {
+    for (const tag of item.tags) {
+      const current = counts.get(tag.key)
+      if (current) current.count += 1
+      else counts.set(tag.key, { tag, count: 1 })
+    }
+  }
+  return [...counts.values()]
+    .sort((a, b) => b.count - a.count || a.tag.label.localeCompare(b.tag.label))
+    .slice(0, limit)
+    .map((entry) => entry.tag)
+}
+
+export function filterByTag(items: TaggedNewsItem[], tagKey: string | null): TaggedNewsItem[] {
+  if (!tagKey) return items
+  return items.filter((item) => item.tags.some((tag) => tag.key === tagKey))
+}
+
+export function tagColour(colour: string): string {
+  if (!colour) return 'var(--text-3)'
+  return colour.startsWith('#') ? colour : `#${colour}`
+}
+
+export function sortWindowBucketsNewestFirst<T extends { window: GPWindow }>(buckets: T[]): T[] {
+  return [...buckets].sort((a, b) => {
+    const left = a.window.start?.getTime() ?? 0
+    const right = b.window.start?.getTime() ?? 0
+    return right - left
+  })
+}

frontend/src/lib/driverProfile.ts

@@ -0,0 +1,69 @@
+import type { DriverSummaryRound } from '../types'
+
+/** One round mapped for the grid-vs-finish chart and results table. */
+export interface RoundDelta {
+  round: number // 1-based round index within the completed season
+  label: string // short GP label, e.g. "Bahrain"
+  grid: number | null
+  finish: number | null
+  /** grid − finish: positive = places gained on Sunday, null when unknowable. */
+  delta: number | null
+  points: number
+  status: 'classified' | 'dnf' | 'dns' | 'dsq' | 'absent'
+}
+
+/** Strip the "Grand Prix" boilerplate so round labels fit chart axes. */
+export function shortGpLabel(meetingName: string): string {
+  const short = meetingName
+    .replace(/\s*grand prix\s*/i, ' ')
+    .replace(/\s+gp\s*$/i, ' ')
+    .trim()
+  return short || meetingName
+}
+
+function roundStatus(r: DriverSummaryRound): RoundDelta['status'] {
+  if (r.dns) return 'dns'
+  if (r.dsq) return 'dsq'
+  if (r.dnf) return 'dnf'
+  if (r.race_position <= 0 && r.grid_position <= 0) return 'absent'
+  return 'classified'
+}
+
+/**
+ * Map summary rounds to grid-vs-finish deltas. Positions of 0 mean "no data"
+ * (driver absent, pit-lane start, …) and become null; a delta is only computed
+ * when both ends are known and the driver actually started the race.
+ */
+export function gridFinishDeltas(rounds: DriverSummaryRound[]): RoundDelta[] {
+  return rounds.map((r, i) => {
+    const status = roundStatus(r)
+    const grid = r.grid_position > 0 ? r.grid_position : null
+    const finish = r.race_position > 0 ? r.race_position : null
+    const delta =
+      grid != null && finish != null && status !== 'dns' && status !== 'absent'
+        ? grid - finish
+        : null
+    return {
+      round: i + 1,
+      label: shortGpLabel(r.meeting_name),
+      grid,
+      finish,
+      delta,
+      points: r.points,
+      status,
+    }
+  })
+}
+
+/** 'P4' for known positions, '—' when unknown. */
+export function formatPosition(pos: number | null): string {
+  return pos != null && pos > 0 ? `P${pos}` : '—'
+}
+
+/** '+3' (gained), '−2' (lost), '=' (held), '—' (unknown). */
+export function formatDelta(delta: number | null): string {
+  if (delta == null) return '—'
+  if (delta > 0) return `+${delta}`
+  if (delta < 0) return `−${Math.abs(delta)}`
+  return '='
+}

frontend/src/lib/gpIdentity.ts

@@ -47,7 +47,9 @@ export function countryDecal(meeting: Meeting | undefined | null): string {
   return name.slice(0, 3).toUpperCase() || '—'
 }
 
-export function countryFlag(meeting: Meeting | undefined | null): string {
+export function countryFlag(
+  meeting: Pick<Meeting, 'country_code' | 'country_flag'> | undefined | null,
+): string {
   if (meeting?.country_flag && !/^https?:\/\//i.test(meeting.country_flag)) return meeting.country_flag
   const code = meeting?.country_code?.toUpperCase()
   const iso2 = code ? CODE3_TO_2[code] : ''

frontend/src/lib/h2h.ts

@@ -0,0 +1,47 @@
+import type { ChampHubDriver } from '../types'
+
+export interface TeammatePair {
+  teamName: string
+  teamColour: string
+  driverA: ChampHubDriver
+  driverB: ChampHubDriver
+  /** Drivers on the team beyond the top two (shown as +N). */
+  extraCount: number
+  /** Absolute win gap — smaller means a closer battle. */
+  closeness: number
+}
+
+/** Pair teammates per team for H2H display; skip single-driver teams. */
+export function teammatePairs(drivers: ReadonlyArray<ChampHubDriver>): TeammatePair[] {
+  const byTeam = new Map<string, ChampHubDriver[]>()
+  for (const d of drivers) {
+    const list = byTeam.get(d.team_name) ?? []
+    list.push(d)
+    byTeam.set(d.team_name, list)
+  }
+
+  const pairs: TeammatePair[] = []
+  for (const [teamName, members] of byTeam) {
+    if (members.length < 2) continue
+
+    const sorted = [...members].sort((a, b) => b.points - a.points)
+    const driverA = sorted[0]
+    const driverB = sorted[1]
+    const winsA = driverA.teammate_wins
+    const winsB = driverB.teammate_wins
+
+    pairs.push({
+      teamName,
+      teamColour: driverA.team_colour,
+      driverA,
+      driverB,
+      extraCount: members.length - 2,
+      closeness: Math.abs(winsA - winsB),
+    })
+  }
+
+  return pairs.sort((a, b) => {
+    if (a.closeness !== b.closeness) return a.closeness - b.closeness
+    return a.teamName.localeCompare(b.teamName)
+  })
+}

frontend/src/lib/preview.ts

@@ -0,0 +1,123 @@
+import type { ChampionshipHub, EnrichedGrid, EnrichedResult, Meeting, Session } from '../types'
+import {
+  currentAndNextSession,
+  nextUpcomingMeeting,
+  sessionStartTime,
+  sortSessionsByStart,
+} from './schedule'
+
+export const RACE_WIN_POINTS = 25
+export const SPRINT_WIN_POINTS = 8
+export const SPRINT_WEEKEND_MAX_POINTS = RACE_WIN_POINTS + SPRINT_WIN_POINTS
+
+export function pickPreviewMeeting(meetings: Meeting[], now: Date): Meeting | null {
+  const active = meetings.filter((m) => !m.is_cancelled)
+  return nextUpcomingMeeting(active, now)
+}
+
+export function findPriorYearMeetingByCircuit(
+  priorYearMeetings: Meeting[],
+  circuitKey: number | undefined,
+): Meeting | null {
+  if (!circuitKey) return null
+  return priorYearMeetings.find((m) => m.circuit_key === circuitKey && !m.is_cancelled) ?? null
+}
+
+export function findRaceSession(sessions: Session[]): Session | null {
+  const sorted = sortSessionsByStart(sessions)
+  return (
+    sorted.find((s) => {
+      const type = s.session_type?.toLowerCase() ?? ''
+      return type.includes('race') && !type.includes('sprint')
+    }) ?? null
+  )
+}
+
+export function isSprintWeekend(sessions: Session[]): boolean {
+  return sessions.some((s) => {
+    const label = `${s.session_type} ${s.session_name}`.toLowerCase()
+    return /\bsprint\b/.test(label) && !label.includes('sprint qualifying') && !label.includes('sprint shootout')
+  })
+}
+
+export interface PodiumPlace {
+  position: number
+  name_acronym: string
+  full_name: string
+  team_name: string
+  team_colour: string
+}
+
+export interface PolePosition {
+  name_acronym: string
+  full_name: string
+  team_name: string
+  team_colour: string
+}
+
+export function extractPodium(results: EnrichedResult[]): PodiumPlace[] {
+  return results
+    .filter((r) => r.position >= 1 && r.position <= 3 && !r.dns && !r.dsq)
+    .sort((a, b) => a.position - b.position)
+    .map((r) => ({
+      position: r.position,
+      name_acronym: r.name_acronym,
+      full_name: r.full_name,
+      team_name: r.team_name,
+      team_colour: r.team_colour,
+    }))
+}
+
+export function extractPole(grid: EnrichedGrid[]): PolePosition | null {
+  const pole = grid.find((g) => g.position === 1)
+  if (!pole) return null
+  return {
+    name_acronym: pole.name_acronym,
+    full_name: pole.full_name,
+    team_name: pole.team_name,
+    team_colour: pole.team_colour,
+  }
+}
+
+export interface TitleFightDriver {
+  name_acronym: string
+  full_name: string
+  team_colour: string
+  points: number
+  position: number
+  gapToLeader: number
+  gapAfterRaceWin: number
+  gapAfterSprintWeekendMax: number
+}
+
+export function buildTitleFightContext(hub: ChampionshipHub): TitleFightDriver[] {
+  if (hub.drivers.length === 0) return []
+  const leader = hub.drivers[0]
+  return hub.drivers.slice(0, 3).map((d) => ({
+    name_acronym: d.name_acronym,
+    full_name: d.full_name,
+    team_colour: d.team_colour,
+    points: d.points,
+    position: d.position,
+    gapToLeader: leader.points - d.points,
+    gapAfterRaceWin: leader.points - (d.points + RACE_WIN_POINTS),
+    gapAfterSprintWeekendMax: leader.points - (d.points + SPRINT_WEEKEND_MAX_POINTS),
+  }))
+}
+
+export function countdownTargetSession(sessions: Session[], now: Date): Session | null {
+  const sorted = sortSessionsByStart(sessions)
+  const { next } = currentAndNextSession(sorted, now)
+  if (next) return next
+  for (const session of sorted) {
+    const start = sessionStartTime(session)
+    if (start && start > now) return session
+  }
+  return null
+}
+
+export function formatPointsGap(gap: number): string {
+  if (gap === 0) return 'LEADER'
+  const sign = gap > 0 ? '+' : ''
+  return `${sign}${Number.isInteger(gap) ? gap : gap.toFixed(1)}`
+}

frontend/src/lib/replay.ts

@@ -0,0 +1,75 @@
+import type { ReplayCarPosition, ReplayFrame, TrackBounds } from '../types'
+import { canvasToSvg, normalizeRawPoint } from './trackmap'
+
+export interface ReplayFramePair {
+  previous: ReplayFrame | null
+  next: ReplayFrame | null
+}
+
+export function lookupReplayFramePair(
+  frames: ReadonlyArray<ReplayFrame>,
+  tMs: number,
+): ReplayFramePair {
+  if (frames.length === 0) return { previous: null, next: null }
+  if (tMs <= frames[0].t) return { previous: frames[0], next: frames[0] }
+  const last = frames[frames.length - 1]
+  if (tMs >= last.t) return { previous: last, next: last }
+
+  let lo = 0
+  let hi = frames.length - 1
+  while (lo <= hi) {
+    const mid = Math.floor((lo + hi) / 2)
+    const frame = frames[mid]
+    if (frame.t === tMs) return { previous: frame, next: frame }
+    if (frame.t < tMs) {
+      lo = mid + 1
+    } else {
+      hi = mid - 1
+    }
+  }
+
+  return { previous: frames[Math.max(0, hi)], next: frames[Math.min(frames.length - 1, lo)] }
+}
+
+export function interpolateReplayCars(
+  frames: ReadonlyArray<ReplayFrame>,
+  tMs: number,
+): Record<string, ReplayCarPosition> {
+  const { previous, next } = lookupReplayFramePair(frames, tMs)
+  if (!previous && !next) return {}
+  if (!previous) return next?.cars ?? {}
+  if (!next || previous.t === next.t) return previous.cars
+
+  const span = next.t - previous.t
+  const fraction = span <= 0 ? 0 : clamp01((tMs - previous.t) / span)
+  const cars: Record<string, ReplayCarPosition> = {}
+  const numbers = new Set([...Object.keys(previous.cars), ...Object.keys(next.cars)])
+
+  for (const number of numbers) {
+    const before = previous.cars[number]
+    const after = next.cars[number]
+    if (before && after) {
+      cars[number] = {
+        x: before.x + (after.x - before.x) * fraction,
+        y: before.y + (after.y - before.y) * fraction,
+      }
+    } else if (before) {
+      cars[number] = before
+    } else if (after) {
+      cars[number] = after
+    }
+  }
+  return cars
+}
+
+export function replayCarToSvg(
+  car: ReplayCarPosition,
+  bounds: TrackBounds,
+): ReplayCarPosition {
+  return canvasToSvg(normalizeRawPoint({ x: car.x, y: car.y }, bounds))
+}
+
+function clamp01(value: number): number {
+  if (!Number.isFinite(value)) return 0
+  return Math.min(1, Math.max(0, value))
+}

frontend/src/lib/replayMap.ts

@@ -0,0 +1,14 @@
+import type { ReplayFramesResponse, TrackOutline } from '../types'
+
+/** Whether replay map can render (probe uses existing frames + outline queries). */
+export function isReplayMapAvailable(
+  replay: ReplayFramesResponse | null | undefined,
+  outline: TrackOutline | null | undefined,
+  hasError: boolean,
+): boolean {
+  if (hasError) return false
+  const frames = replay?.frames ?? []
+  if (frames.length < 2) return false
+  if (!outline?.points?.length) return false
+  return true
+}

frontend/src/lib/rivalry.ts

@@ -0,0 +1,61 @@
+// Pure helpers for the championship rivalry compare view.
+
+/** One round that counted toward the head-to-head tally. */
+export interface H2HRound {
+  round: number // 1-based season round
+  label: string
+  posA: number
+  posB: number
+  winner: 'a' | 'b'
+}
+
+export interface H2HTally {
+  a: number
+  b: number
+  /** Rounds counted in the tally, in season order. */
+  rounds: H2HRound[]
+  /** Rounds skipped because either driver had no finishing position. */
+  skipped: number
+}
+
+/**
+ * Per-round points gap (a − b) across the rounds both cumulative series
+ * cover. Positive values mean driver A is ahead.
+ */
+export function gapSeries(a: number[], b: number[]): number[] {
+  const n = Math.min(a.length, b.length)
+  const out: number[] = []
+  for (let i = 0; i < n; i++) out.push(a[i] - b[i])
+  return out
+}
+
+/**
+ * Race head-to-head: per round, the lower finishing position wins. Rounds
+ * where either driver has no position (0 / missing) are skipped from the
+ * tally, as are equal positions (defensive — races can't tie).
+ */
+export function h2hTally(posA: number[], posB: number[], labels: string[]): H2HTally {
+  const n = Math.max(posA.length, posB.length)
+  const rounds: H2HRound[] = []
+  let a = 0
+  let b = 0
+  let skipped = 0
+  for (let i = 0; i < n; i++) {
+    const pa = posA[i] ?? 0
+    const pb = posB[i] ?? 0
+    if (pa <= 0 || pb <= 0 || pa === pb) {
+      skipped++
+      continue
+    }
+    const winner = pa < pb ? 'a' : 'b'
+    if (winner === 'a') a++
+    else b++
+    rounds.push({ round: i + 1, label: labels[i] ?? `R${i + 1}`, posA: pa, posB: pb, winner })
+  }
+  return { a, b, rounds, skipped }
+}
+
+/** Last n counted rounds of a tally, for the mini strip. */
+export function lastRounds(tally: H2HTally, n: number): H2HRound[] {
+  return tally.rounds.slice(-n)
+}

frontend/src/lib/routeSearch.ts

@@ -0,0 +1,40 @@
+/** Shared URL search contracts for deep-linkable Weekend ↔ Race Hub navigation. */
+
+export type WeekendSearch = {
+  meeting_key?: number
+  session_key?: number
+}
+
+export type RaceHubSearch = {
+  session_key?: number
+}
+
+function parsePositiveInt(value: unknown): number | undefined {
+  const n = Number(value)
+  return Number.isFinite(n) && n > 0 ? n : undefined
+}
+
+export function parseWeekendSearch(search: Record<string, unknown>): WeekendSearch {
+  const meeting_key = parsePositiveInt(search.meeting_key)
+  const session_key = parsePositiveInt(search.session_key)
+  return {
+    ...(meeting_key ? { meeting_key } : {}),
+    ...(session_key ? { session_key } : {}),
+  }
+}
+
+export function parseRaceHubSearch(search: Record<string, unknown>): RaceHubSearch {
+  const session_key = parsePositiveInt(search.session_key)
+  return session_key ? { session_key } : {}
+}
+
+/** Build Weekend `/` search so a Race Hub return is reload-safe and deep-linkable. */
+export function weekendFocusSearch(
+  meetingKey?: number | null,
+  sessionKey?: number | null,
+): WeekendSearch {
+  return {
+    ...(meetingKey && meetingKey > 0 ? { meeting_key: meetingKey } : {}),
+    ...(sessionKey && sessionKey > 0 ? { session_key: sessionKey } : {}),
+  }
+}

frontend/src/lib/sessionState.ts

@@ -0,0 +1,194 @@
+import type { ContextSession, WeekendContext, WeekendSession } from '../types'
+import { isSessionComplete } from './coverage'
+import { sessionStartTime } from './schedule'
+
+/**
+ * User-facing lifecycle state for a weekend session.
+ *
+ * Live comes only from Weekend Context's FIA-backed active identity — never from
+ * the scheduled start/end window alone. Preparing / partial / ready / unavailable
+ * come from structured `availability.local_analysis` when a context ref exists,
+ * otherwise from local dataset coverage after the scheduled start.
+ */
+export type SessionState =
+  | 'upcoming'
+  | 'live'
+  | 'preparing'
+  | 'partial'
+  | 'ready'
+  | 'unavailable'
+  | 'cancelled'
+
+export interface SessionStateInput {
+  weekendSession?: WeekendSession
+  context?: WeekendContext | null
+  now: Date
+}
+
+function contextRefFor(
+  context: WeekendContext | null | undefined,
+  sessionKey: number | undefined,
+): ContextSession | undefined {
+  if (!context || !sessionKey) return undefined
+  const refs = [
+    context.active_session,
+    context.default_analysis_session,
+    context.previous_completed_session,
+    context.next_session,
+  ]
+  return refs.find((ref) => ref?.session.session_key === sessionKey)
+}
+
+function fromAvailability(ref: ContextSession): SessionState | undefined {
+  const { schedule, live_session, local_analysis } = ref.availability
+  if (live_session === 'active') return 'live'
+  if (schedule === 'unavailable' || local_analysis === 'unavailable') return 'unavailable'
+  if (local_analysis === 'not_applicable') return 'upcoming'
+  if (local_analysis === 'pending') return 'preparing'
+  if (local_analysis === 'partial') return 'partial'
+  if (local_analysis === 'complete') return 'ready'
+  return undefined
+}
+
+/**
+ * Resolve fan-facing session state. Prefer Weekend Context availability; never
+ * assert Live from wall-clock schedule alone.
+ */
+export function resolveSessionState({
+  weekendSession,
+  context,
+  now,
+}: SessionStateInput): SessionState {
+  if (weekendSession?.source === 'cancelled') return 'cancelled'
+
+  const sessionKey = weekendSession?.session.session_key
+  const active = context?.active_session
+  if (
+    active &&
+    sessionKey &&
+    active.session.session_key === sessionKey &&
+    active.availability.live_session === 'active'
+  ) {
+    return 'live'
+  }
+
+  const ref = contextRefFor(context, sessionKey)
+  if (ref) {
+    const fromCtx = fromAvailability(ref)
+    if (fromCtx) return fromCtx
+  }
+
+  // Settling temporal state with no analysis yet — even without a matching ref.
+  if (
+    context?.temporal_state === 'session_settling' &&
+    weekendSession &&
+    weekendSession.source === 'none'
+  ) {
+    return 'preparing'
+  }
+
+  if (!weekendSession) return 'unavailable'
+
+  const start = sessionStartTime(weekendSession.session)
+  if (start && start > now) return 'upcoming'
+
+  if (isSessionComplete(weekendSession.datasets)) return 'ready'
+  if (weekendSession.source === 'none') return 'preparing'
+  if (weekendSession.source === 'partial') return 'partial'
+  return 'ready'
+}
+
+/** @deprecated Prefer resolveSessionState with Weekend Context. */
+export function sessionState(session: WeekendSession, now: Date): SessionState {
+  return resolveSessionState({ weekendSession: session, now })
+}
+
+/** Short label suitable for chips and the session switcher. */
+export function sessionStateLabel(state: SessionState): string {
+  switch (state) {
+    case 'upcoming':
+      return 'Upcoming'
+    case 'live':
+      return 'Live'
+    case 'preparing':
+      return 'Preparing'
+    case 'partial':
+      return 'Partial'
+    case 'ready':
+      return 'Ready'
+    case 'unavailable':
+      return 'Unavailable'
+    case 'cancelled':
+      return 'Cancelled'
+  }
+}
+
+/** Longer, sentence-style description for headers and empty states. */
+export function sessionStateDescription(state: SessionState): string {
+  switch (state) {
+    case 'upcoming':
+      return 'Session has not started yet.'
+    case 'live':
+      return 'Session is running now.'
+    case 'preparing':
+      return 'Analysis is being prepared — local data is still settling.'
+    case 'partial':
+      return 'Partial analysis available — some datasets are still missing.'
+    case 'ready':
+      return 'Full analysis is ready.'
+    case 'unavailable':
+      return 'Analysis is not available for this session.'
+    case 'cancelled':
+      return 'This session was cancelled.'
+  }
+}
+
+/**
+ * Class suffix used for the coverage dot, so the rail can colour a session by
+ * its lifecycle state rather than only by data source.
+ */
+export function sessionStateDotClass(state: SessionState): string {
+  switch (state) {
+    case 'ready':
+      return 'rh-state-ready'
+    case 'partial':
+      return 'rh-state-partial'
+    case 'live':
+      return 'rh-state-live'
+    case 'upcoming':
+      return 'rh-state-upcoming'
+    case 'unavailable':
+      return 'rh-state-unavailable'
+    case 'cancelled':
+      return 'rh-state-cancelled'
+    default:
+      return 'rh-state-preparing'
+  }
+}
+
+/** Whether a session should render the pre-session (expected availability) view. */
+export function isPreSession(state: SessionState): boolean {
+  return state === 'upcoming'
+}
+
+/** Settling / empty post-session — not yet analysable. */
+export function isPreparing(state: SessionState): boolean {
+  return state === 'preparing'
+}
+
+export function isUnavailable(state: SessionState): boolean {
+  return state === 'unavailable' || state === 'cancelled'
+}
+
+/** Show fan analysis with a partial banner; keep available capabilities. */
+export function isPartialAnalysis(state: SessionState): boolean {
+  return state === 'partial'
+}
+
+/** Canonical default analysis session key from Weekend Context, if any. */
+export function defaultAnalysisSessionKey(
+  context: WeekendContext | null | undefined,
+): number | undefined {
+  const key = context?.default_analysis_session?.session.session_key
+  return key && key > 0 ? key : undefined
+}

frontend/src/lib/weekendContext.ts

@@ -0,0 +1,181 @@
+import type {
+  ChampionshipHub,
+  ContextSession,
+  EnrichedResult,
+  Meeting,
+  NewsItem,
+  Session,
+  WeekendBriefingItem,
+  WeekendChampionshipImpact,
+  WeekendChampionshipMover,
+  WeekendContext,
+  WeekendPodiumEntry,
+  WeekendViewState,
+} from '../types'
+
+/**
+ * resolveViewState maps the canonical `temporal_state` onto the rendered Weekend
+ * view. It is a total function: every valid canonical `temporal_state` resolves
+ * to a concrete view, so a well-formed payload never falls through to a
+ * limited/empty placeholder. Loading and error are hook-level states that are
+ * not part of the #72 contract.
+ */
+export function resolveViewState(context: WeekendContext): WeekendViewState {
+  switch (context.temporal_state) {
+    case 'no_season':
+      return 'no_season'
+    case 'between_weekends':
+      return 'between_weekends'
+    case 'pre_session':
+      return 'pre_session'
+    case 'session_live':
+      return 'session_live'
+    case 'session_settling':
+      return 'session_settling'
+    case 'between_sessions':
+      return 'between_sessions'
+    case 'post_weekend':
+      return 'post_weekend'
+    case 'season_complete':
+      return 'season_complete'
+    default:
+      // Unknown/absent temporal_state is an invalid payload — treat as no_season
+      // rather than inventing a state. The hook still shows an explicit surface.
+      return 'no_season'
+  }
+}
+
+export interface MeetingIdentity {
+  meeting_key: number
+  meeting_name: string
+  short_name: string
+  country_code: string
+  country_flag: string
+  circuit_short_name: string
+  circuit_key?: number
+  date_start?: string
+  date_end?: string
+}
+
+/** Presentation identity for a meeting, tolerant of partial/absent fields. */
+export function meetingIdentity(meeting: Meeting | undefined): MeetingIdentity | undefined {
+  if (!meeting) return undefined
+  return {
+    meeting_key: meeting.meeting_key,
+    meeting_name: meeting.meeting_name || meeting.location || 'Grand Prix',
+    short_name: (meeting.meeting_name || meeting.location || 'Grand Prix').replace(/ Grand Prix$/i, ''),
+    country_code: meeting.country_code,
+    country_flag: meeting.country_flag,
+    circuit_short_name: meeting.circuit_short_name || meeting.location || '',
+    circuit_key: meeting.circuit_key,
+    date_start: meeting.date_start || undefined,
+    date_end: meeting.date_end || undefined,
+  }
+}
+
+/** Session identity paired with its resolved meeting for a canonical ContextSession. */
+export function sessionMeeting(ref: ContextSession | undefined): Meeting | undefined {
+  return ref?.meeting
+}
+
+export function sessionOf(ref: ContextSession | undefined): Session | undefined {
+  return ref?.session
+}
+
+/**
+ * analysisSessionKey resolves the session a user should open to read analysis for
+ * a completed event. It prefers the canonical default analysis session, falling
+ * back to the previous completed session. Returns undefined when nothing analysable
+ * is available (e.g. an archived result with no local analysis).
+ */
+export function analysisSessionKey(context: WeekendContext): number | undefined {
+  const key =
+    context.default_analysis_session?.session.session_key ??
+    context.previous_completed_session?.session.session_key
+  return key && key > 0 ? key : undefined
+}
+
+/** True when a ContextSession has local analysis worth linking to. */
+export function hasLocalAnalysis(ref: ContextSession | undefined): boolean {
+  const status = ref?.availability.local_analysis
+  return status === 'complete' || status === 'partial'
+}
+
+/** Countdown target for a session reference — its scheduled start, if known. */
+export function sessionStart(ref: ContextSession | undefined): string | undefined {
+  const start = ref?.session.date_start
+  return start ? start : undefined
+}
+
+export function podiumFromResults(results: EnrichedResult[]): WeekendPodiumEntry[] {
+  return [...results]
+    .filter((r) => r.position >= 1)
+    .sort((a, b) => a.position - b.position)
+    .slice(0, 3)
+    .map((r) => ({
+      position: r.position,
+      driver_number: r.driver_number,
+      name_acronym: r.name_acronym,
+      team_name: r.team_name,
+      team_colour: r.team_colour,
+      gap: formatResultGap(r),
+    }))
+}
+
+function formatResultGap(r: EnrichedResult): string {
+  if (r.dnf) return 'DNF'
+  if (r.dns) return 'DNS'
+  if (r.dsq) return 'DSQ'
+  if (r.position === 1) {
+    if (typeof r.duration === 'number' && r.duration > 0) return formatDuration(r.duration)
+    return 'Winner'
+  }
+  const gap = Array.isArray(r.gap_to_leader) ? r.gap_to_leader[r.gap_to_leader.length - 1] : r.gap_to_leader
+  if (typeof gap === 'number') return `+${gap.toFixed(3)}`
+  if (typeof gap === 'string' && gap) return gap.startsWith('+') ? gap : `+${gap}`
+  return '—'
+}
+
+function formatDuration(seconds: number): string {
+  const h = Math.floor(seconds / 3600)
+  const m = Math.floor((seconds % 3600) / 60)
+  const s = seconds % 60
+  if (h > 0) return `${h}:${String(m).padStart(2, '0')}:${s.toFixed(3).padStart(6, '0')}`
+  return `${m}:${s.toFixed(3).padStart(6, '0')}`
+}
+
+/**
+ * championshipImpact derives the top-of-standings movers from the championship
+ * hub. This is supplementary data layered onto the canonical context, not part of
+ * the #72 contract.
+ */
+export function championshipImpact(hub: ChampionshipHub | undefined): WeekendChampionshipImpact | undefined {
+  if (!hub || hub.drivers.length === 0) return undefined
+  const leaders: WeekendChampionshipMover[] = hub.drivers.slice(0, 3).map((d) => {
+    const cumulative = d.cumulative ?? []
+    const delta =
+      cumulative.length >= 2 ? cumulative[cumulative.length - 1] - cumulative[cumulative.length - 2] : undefined
+    return {
+      position: d.position,
+      driver_number: d.driver_number,
+      name_acronym: d.name_acronym,
+      team_colour: d.team_colour,
+      points: d.points,
+      delta,
+    }
+  })
+  const note = hub.last_race ? `Standings after ${hub.last_race}.` : undefined
+  return { leaders, note }
+}
+
+/** At most three briefing items, mapped from the news feed. */
+export function briefingItems(news: NewsItem[]): WeekendBriefingItem[] {
+  return news.slice(0, 3).map((item) => ({
+    category: item.category,
+    title: item.title,
+    url: item.url,
+    source: item.source,
+    published_at: item.published_at,
+    image_url: item.og_image_url,
+  }))
+}

frontend/src/pages/BriefingPage.tsx

@@ -1,13 +1,33 @@
-import { useCallback, useEffect, useRef, useState } from 'react'
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
 import { useQuery, useQueryClient } from '@tanstack/react-query'
-import { fetchNews, fetchNewsArticle, markNewsRead } from '../api'
+import {
+  fetchChampionshipHub,
+  fetchNews,
+  fetchNewsArticle,
+  fetchSeasonMeetings,
+  fetchSeasons,
+  markNewsRead,
+} from '../api'
+import {
+  activeDigestWindow,
+  filterByTag,
+  groupByWindow,
+  gpWindows,
+  itemsForWindow,
+  sinceLastLabel,
+  sortWindowBucketsNewestFirst,
+  tagColour,
+  tagItems,
+  topTags,
+  type DigestTag,
+  type TaggedNewsItem,
+} from '../lib/digest'
 import { stripHtml, timeAgo } from '../utils'
 import type { ArticleContent, NewsItem } from '../types'
+import '../styles/digest.css'
 
 type Category = 'all' | 'official' | 'news' | 'video'
 
-const PAGE_SIZE = 16
-
 const CATEGORY_LABELS: Record<Category, string> = {
   all: 'All',
   official: 'Official',
@@ -71,6 +91,31 @@ function CategoryTabs({
   )
 }
 
+function TagChip({
+  tag,
+  active,
+  onClick,
+  className = 'digest-tag-chip',
+}: {
+  tag: DigestTag
+  active?: boolean
+  onClick?: () => void
+  className?: string
+}) {
+  return (
+    <button
+      type="button"
+      className={`${className}${active ? ' active' : ''}`}
+      style={{ '--tag-colour': tagColour(tag.colour) } as React.CSSProperties}
+      onClick={onClick}
+      aria-pressed={active}
+    >
+      <span className="digest-tag-dot" aria-hidden="true" />
+      {tag.label}
+    </button>
+  )
+}
+
 function OGImage({ url, title }: { url?: string; title: string }) {
   const [failed, setFailed] = useState(false)
   const initial = (title[0] ?? '?').toUpperCase()
@@ -98,11 +143,15 @@ function OGImage({ url, title }: { url?: string; title: string }) {
 function BriefingCard({
   item,
   isActive,
+  activeTag,
   onSelect,
+  onTagClick,
 }: {
-  item: NewsItem
+  item: TaggedNewsItem
   isActive: boolean
+  activeTag: string | null
   onSelect: (item: NewsItem) => void
+  onTagClick: (tag: DigestTag) => void
 }) {
   const isRead = !!item.read_at
   const isVideo = categoryOf(item) === 'video'
@@ -129,6 +178,25 @@ function BriefingCard({
             {stripHtml(item.og_description || item.summary || '')}
           </p>
         )}
+        {item.tags.length > 0 && (
+          <div className="bp-card-tags">
+            {item.tags.map((tag) => (
+              <button
+                key={tag.key}
+                type="button"
+                className={`bp-card-tag${activeTag === tag.key ? ' active' : ''}`}
+                style={{ '--tag-colour': tagColour(tag.colour) } as React.CSSProperties}
+                onClick={(e) => {
+                  e.stopPropagation()
+                  onTagClick(tag)
+                }}
+              >
+                <span className="digest-tag-dot" aria-hidden="true" />
+                {tag.label}
+              </button>
+            ))}
+          </div>
+        )}
       </div>
     </article>
   )
@@ -146,7 +214,6 @@ function ReaderPanel({
   const [loading, setLoading] = useState(false)
   const [error, setError] = useState<string | null>(null)
 
-  // Close on Escape
   useEffect(() => {
     const handler = (e: KeyboardEvent) => {
       if (e.key === 'Escape') onClose()
@@ -155,7 +222,6 @@ function ReaderPanel({
     return () => document.removeEventListener('keydown', handler)
   }, [onClose])
 
-  // Fetch article when item changes
   useEffect(() => {
     if (!item) {
       setArticle(null)
@@ -175,9 +241,14 @@ function ReaderPanel({
       .catch((err) => { setError(String(err)); setLoading(false) })
   }, [item?.url, item ? categoryOf(item) : ''])
 
-  // Scroll panel to top when item changes
   useEffect(() => {
-    panelRef.current?.scrollTo({ top: 0 })
+    const panel = panelRef.current
+    if (!panel) return
+    if (typeof panel.scrollTo === 'function') {
+      panel.scrollTo({ top: 0 })
+    } else {
+      panel.scrollTop = 0
+    }
   }, [item?.url])
 
   const isOpen = item !== null
@@ -297,7 +368,6 @@ function ReaderPanel({
               {article && !loading && article.content && (
                 <div
                   className="bp-reader-body"
-                  // readability strips scripts/iframes; sources are all known news outlets
                   // eslint-disable-next-line react/no-danger
                   dangerouslySetInnerHTML={{ __html: article.content }}
                 />
@@ -332,8 +402,9 @@ function ReaderPanel({
 export function BriefingPage() {
   const [activeCategory, setActiveCategory] = useState<Category>('all')
   const [selectedItem, setSelectedItem] = useState<NewsItem | null>(null)
-  const [page, setPage] = useState(1)
+  const [activeTag, setActiveTag] = useState<string | null>(null)
   const queryClient = useQueryClient()
+  const now = useMemo(() => new Date(), [])
 
   const { data: allNews = [], isLoading, isError } = useQuery({
     queryKey: ['news'],
@@ -341,13 +412,74 @@ export function BriefingPage() {
     staleTime: 60_000,
   })
 
-  const filtered = allNews.filter(
+  const seasonsQuery = useQuery({
-    (item) => activeCategory === 'all' || categoryOf(item) === activeCategory,
+    queryKey: ['seasons'],
+    queryFn: fetchSeasons,
+  })
+  const latestSeason = seasonsQuery.data?.[0] ?? null
+
+  const meetingsQuery = useQuery({
+    queryKey: ['season-meetings', latestSeason],
+    queryFn: () => fetchSeasonMeetings(latestSeason!),
+    enabled: latestSeason != null,
+  })
+
+  const hubQuery = useQuery({
+    queryKey: ['championship-hub', latestSeason],
+    queryFn: () => fetchChampionshipHub(latestSeason!),
+    enabled: latestSeason != null,
+  })
+
+  const meetings = meetingsQuery.data ?? []
+  const hub = hubQuery.data
+
+  const taggedNews = useMemo(
+    () => tagItems(allNews, hub?.drivers ?? [], hub?.teams ?? []),
+    [allNews, hub],
   )
-  const pageCount = Math.max(1, Math.ceil(filtered.length / PAGE_SIZE))
+
-  const safePage = Math.min(page, pageCount)
+  const categoryFiltered = useMemo(
-  const pageStart = (safePage - 1) * PAGE_SIZE
+    () => taggedNews.filter(
-  const pagedItems = filtered.slice(pageStart, pageStart + PAGE_SIZE)
+      (item) => activeCategory === 'all' || categoryOf(item) === activeCategory,
+    ),
+    [taggedNews, activeCategory],
+  )
+
+  const tagFiltered = useMemo(
+    () => filterByTag(categoryFiltered, activeTag),
+    [categoryFiltered, activeTag],
+  )
+
+  const windows = useMemo(() => gpWindows(meetings, now), [meetings, now])
+  const grouped = useMemo(() => groupByWindow(tagFiltered, windows), [tagFiltered, windows])
+  const windowSections = useMemo(
+    () => sortWindowBucketsNewestFirst(grouped.windows),
+    [grouped.windows],
+  )
+
+  const activeWindow = useMemo(
+    () => activeDigestWindow(windows, meetings, now),
+    [windows, meetings, now],
+  )
+
+  const sinceLastItems = useMemo(
+    () => itemsForWindow(tagFiltered, activeWindow),
+    [tagFiltered, activeWindow],
+  )
+
+  const sinceLastTags = useMemo(() => topTags(sinceLastItems), [sinceLastItems])
+  const sinceLabel = sinceLastLabel(meetings, now)
+
+  const taggedByUrl = useMemo(() => {
+    const map = new Map<string, TaggedNewsItem>()
+    for (const item of tagFiltered) map.set(item.url, item)
+    return map
+  }, [tagFiltered])
+
+  const recentTagged = useMemo(() => {
+    const urls = new Set(grouped.recent.map((item) => item.url))
+    return tagFiltered.filter((item) => urls.has(item.url))
+  }, [grouped.recent, tagFiltered])
 
   const counts: Record<Category, number> = {
     all: allNews.length,
@@ -374,22 +506,14 @@ export function BriefingPage() {
 
   const handleClose = useCallback(() => setSelectedItem(null), [])
 
-  useEffect(() => {
+  const handleTagClick = useCallback((tag: DigestTag) => {
-    setPage((current) => Math.min(current, pageCount))
+    setActiveTag((current) => (current === tag.key ? null : tag.key))
-  }, [pageCount])
+    setSelectedItem(null)
-
+  }, [])
-  const handlePageChange = useCallback(
-    (nextPage: number) => {
-      setPage(Math.min(Math.max(nextPage, 1), pageCount))
-      setSelectedItem(null)
-      window.scrollTo({ top: 0, behavior: 'smooth' })
-    },
-    [pageCount],
-  )
 
   const unreadCount = allNews.filter((i) => !i.read_at).length
-  const pageEnd = Math.min(pageStart + pagedItems.length, filtered.length)
+  const hasDigest = meetings.length > 0
-  const showPagination = filtered.length > PAGE_SIZE
+  const showEmpty = tagFiltered.length === 0 && grouped.recent.length === 0
 
   return (
     <div className="bp-page" data-testid="briefing-page">
@@ -408,74 +532,106 @@ export function BriefingPage() {
           <CategoryTabs
             active={activeCategory}
             counts={counts}
-            onChange={(c) => { setActiveCategory(c); setSelectedItem(null); setPage(1) }}
+            onChange={(c) => {
+              setActiveCategory(c)
+              setSelectedItem(null)
+              setActiveTag(null)
+            }}
           />
 
-          {filtered.length === 0 ? (
+          {hasDigest && (
+            <div className="digest-sticky" data-testid="digest-sticky-header">
+              <div className="digest-sticky-head">
+                <h2 className="digest-sticky-title">Since {sinceLabel}</h2>
+                <span className="digest-sticky-count">
+                  {sinceLastItems.length} item{sinceLastItems.length === 1 ? '' : 's'}
+                </span>
+              </div>
+              {(sinceLastTags.length > 0 || activeTag) && (
+                <div className="digest-sticky-tags">
+                  {sinceLastTags.map((tag) => (
+                    <TagChip
+                      key={tag.key}
+                      tag={tag}
+                      active={activeTag === tag.key}
+                      onClick={() => handleTagClick(tag)}
+                    />
+                  ))}
+                  {activeTag && (
+                    <button
+                      type="button"
+                      className="digest-filter-clear"
+                      onClick={() => setActiveTag(null)}
+                      data-testid="digest-filter-clear"
+                    >
+                      Clear filter
+                    </button>
+                  )}
+                </div>
+              )}
+            </div>
+          )}
+
+          {showEmpty ? (
             <div className="bp-empty">
               No {activeCategory !== 'all' ? activeCategory : ''} items available.
-              Run <code>box-box --ingest-news</code> to refresh feeds.
+              {activeTag ? ' Try clearing the tag filter.' : ''}
+              {!activeTag && (
+                <>
+                  {' '}
+                  Run <code>box-box --ingest-news</code> to refresh feeds.
+                </>
+              )}
             </div>
           ) : (
             <>
-              {showPagination && (
+              {windowSections.map(({ window, items }) => (
-                <div className="bp-pagination bp-pagination-top">
+                <section
-                  <span className="bp-pagination-meta mono">
+                  key={window.meeting_key}
-                    {pageStart + 1}-{pageEnd} of {filtered.length}
+                  className="digest-section"
-                  </span>
+                  data-testid={`digest-window-${window.meeting_key}`}
-                  <div className="bp-pagination-actions">
+                >
-                    <button
+                  <div className="digest-section-head">
-                      className="bp-page-btn"
+                    <h3 className="digest-section-title">{window.meeting_name}</h3>
-                      onClick={() => handlePageChange(safePage - 1)}
+                    <span className="digest-section-count">{items.length}</span>
-                      disabled={safePage === 1}
-                    >
-                      Previous
-                    </button>
-                    <span className="bp-page-current mono">
-                      Page {safePage} / {pageCount}
-                    </span>
-                    <button
-                      className="bp-page-btn"
-                      onClick={() => handlePageChange(safePage + 1)}
-                      disabled={safePage === pageCount}
-                    >
-                      Next
-                    </button>
                   </div>
-                </div>
+                  <div className={`bp-grid${selectedItem ? ' bp-grid-narrow' : ''}`}>
-              )}
+                    {items.map((item) => {
+                      const tagged = taggedByUrl.get(item.url) ?? { ...item, tags: [] }
+                      return (
+                        <BriefingCard
+                          key={item.url}
+                          item={tagged}
+                          isActive={selectedItem?.url === item.url}
+                          activeTag={activeTag}
+                          onSelect={handleSelect}
+                          onTagClick={handleTagClick}
+                        />
+                      )
+                    })}
+                  </div>
+                </section>
+              ))}
 
-              <div className={`bp-grid${selectedItem ? ' bp-grid-narrow' : ''}`}>
+              {recentTagged.length > 0 && (
-                {pagedItems.map((item) => (
+                <section className="digest-section digest-recent-section" data-testid="digest-recent">
-                  <BriefingCard
+                  <div className="digest-section-head">
-                    key={item.url}
+                    <h3 className="digest-section-title">Recent</h3>
-                    item={item}
+                    <span className="digest-section-count">{recentTagged.length}</span>
-                    isActive={selectedItem?.url === item.url}
+                  </div>
-                    onSelect={handleSelect}
+                  <div className={`bp-grid${selectedItem ? ' bp-grid-narrow' : ''}`}>
-                  />
+                    {recentTagged.map((item) => (
-                ))}
+                      <BriefingCard
-              </div>
+                        key={item.url}
-
+                        item={item}
-              {showPagination && (
+                        isActive={selectedItem?.url === item.url}
-                <div className="bp-pagination bp-pagination-bottom">
+                        activeTag={activeTag}
-                  <button
+                        onSelect={handleSelect}
-                    className="bp-page-btn"
+                        onTagClick={handleTagClick}
-                    onClick={() => handlePageChange(safePage - 1)}
+                      />
-                    disabled={safePage === 1}
+                    ))}
-                  >
+                  </div>
-                    Previous
+                </section>
-                  </button>
-                  <span className="bp-page-current mono">
-                    Page {safePage} / {pageCount}
-                  </span>
-                  <button
-                    className="bp-page-btn"
-                    onClick={() => handlePageChange(safePage + 1)}
-                    disabled={safePage === pageCount}
-                  >
-                    Next
-                  </button>
-                </div>
               )}
             </>
           )}

frontend/src/pages/ChampionshipPage.tsx

@@ -1,13 +1,17 @@
 import { useMemo, useState } from 'react'
 import { useQuery } from '@tanstack/react-query'
+import { Link } from '@tanstack/react-router'
 import { fetchChampionshipHub, fetchSeasons } from '../api'
 import { teamColor } from '../utils'
 import type { ChampHubDriver, ChampionshipHub } from '../types'
 import { ChampionshipSimulator } from '../components/ChampionshipSimulator'
+import { RivalryCompare } from '../components/RivalryCompare'
 import { Meaning } from '../components/Meaning'
+import { TeammateH2H } from '../components/TeammateH2H'
+import { teammatePairs } from '../lib/h2h'
 import { pointsGapMeaning } from '../lib/meaning'
 
-type View = 'drivers' | 'constructors' | 'progression' | 'simulator'
+type View = 'drivers' | 'constructors' | 'progression' | 'rivalry' | 'simulator'
 
 const GOLD = '#ffd700'
 const SILVER = '#c0c0c0'
@@ -213,6 +217,14 @@ function ChampionshipBody({ hub, view, setView }: BodyProps) {
           >
             Progression
           </button>
+          <button
+            type="button"
+            className={`champ-tab${view === 'rivalry' ? ' is-active' : ''}`}
+            onClick={() => setView('rivalry')}
+            data-testid="champ-tab-rivalry"
+          >
+            Rivalry
+          </button>
           <button
             type="button"
             className={`champ-tab${view === 'simulator' ? ' is-active' : ''}`}
@@ -242,10 +254,13 @@ function ChampionshipBody({ hub, view, setView }: BodyProps) {
           leaderPoints={leader.points}
           titleMath={titleMath}
           roundsLeft={hub.rounds_left}
+          drivers={drivers}
+          season={hub.season}
         />
       )}
       {view === 'constructors' && <ConstructorsView hub={hub} />}
       {view === 'progression' && <ProgressionView hub={hub} />}
+      {view === 'rivalry' && <RivalryCompare hub={hub} />}
       {view === 'simulator' && <ChampionshipSimulator hub={hub} />}
     </div>
   )
@@ -271,13 +286,19 @@ function DriversView({
   leaderPoints,
   titleMath,
   roundsLeft,
+  drivers,
+  season,
 }: {
   enriched: EnrichedDriver[]
   leaderPoints: number
   titleMath: string
   roundsLeft: number
+  drivers: ChampHubDriver[]
+  season: number
 }) {
   const podium = enriched.slice(0, 3)
+  const h2hPairs = useMemo(() => teammatePairs(drivers), [drivers])
+
   return (
     <div data-testid="champ-view-drivers">
       <div className="champ-podium">
@@ -336,6 +357,29 @@ function DriversView({
         <span className="champ-titlemath-text">{titleMath}</span>
       </div>
 
+      {h2hPairs.length > 0 && (
+        <section className="h2h-section" data-testid="champ-teammate-battles">
+          <div className="h2h-section-head">
+            <h2 className="h2h-section-title">Teammate battles</h2>
+            <span className="h2h-section-sub">race finishes · closest first</span>
+          </div>
+          <div className="h2h-list">
+            {h2hPairs.map((pair) => (
+              <TeammateH2H
+                key={pair.teamName}
+                teamName={pair.teamName}
+                teamColour={pair.teamColour}
+                driverATla={pair.driverA.name_acronym}
+                driverBTla={pair.driverB.name_acronym}
+                winsA={pair.driverA.teammate_wins}
+                winsB={pair.driverB.teammate_wins}
+                extraNote={pair.extraCount > 0 ? `+${pair.extraCount}` : undefined}
+              />
+            ))}
+          </div>
+        </section>
+      )}
+
       <div className="champ-scroll">
         <table className="champ-table champ-table-drivers">
           <thead>
@@ -360,12 +404,19 @@ function DriversView({
                   P{e.pos}
                 </td>
                 <td>
-                  <div className="champ-drv">
+                  <Link
+                    to="/drivers/$driverNumber"
+                    params={{ driverNumber: String(e.d.driver_number) }}
+                    search={{ year: season }}
+                    className="champ-drv"
+                    style={{ color: 'inherit', textDecoration: 'none' }}
+                    data-testid={`champ-driver-link-${e.d.driver_number}`}
+                  >
                     <span className="champ-drv-bar" style={{ background: e.color }} />
                     <span className="champ-drv-code mono">{e.d.name_acronym}</span>
                     <span className="champ-drv-name">{e.d.full_name}</span>
                     <span className="champ-drv-num mono">#{e.d.driver_number}</span>
-                  </div>
+                  </Link>
                 </td>
                 <td className="champ-td-team">{e.d.team_name}</td>
                 <td className="r mono champ-td-pts">{fmtPts(e.d.points)}</td>

frontend/src/pages/CommandCenterPage.tsx

@@ -1,451 +0,0 @@
-import { useEffect, useMemo, useState } from 'react'
-import { useQueries, useQuery } from '@tanstack/react-query'
-import { Link } from '@tanstack/react-router'
-import {
-  fetchChampionshipHub,
-  fetchLiveState,
-  fetchLocalMeetings,
-  fetchRaceHub,
-  fetchSeasonMeetings,
-  fetchSeasons,
-  fetchSessions,
-  fetchWeekend,
-} from '../api'
-import { CommandCenterHero } from '../components/CommandCenterHero'
-import { PaddockBriefing } from '../components/PaddockBriefing'
-import { RACE_HUB_DATASETS, countWeekendStats, formatCoverageHint, sessionTypeAbbrev } from '../lib/coverage'
-import { countryAccent, countryDecal, countryFlag, formatGpDateRange } from '../lib/gpIdentity'
-import { classifySessionStatus, heroState } from '../lib/hero'
-import {
-  currentAndNextSession,
-  focusMeetingKind,
-  formatSessionScheduleTime,
-  meetingHasStarted,
-  mostRecentPastMeeting,
-  nextUpcomingMeeting,
-  pickFocusMeeting,
-  sortSessionsByStart,
-} from '../lib/schedule'
-import type { Meeting, Session, Weekend, WeekendSession } from '../types'
-import { Trophy } from 'lucide-react'
-
-const missingDatasets = Object.fromEntries(
-  RACE_HUB_DATASETS.map((dataset) => [dataset, { status: 'missing', source: 'none', count: 0 }]),
-) as WeekendSession['datasets']
-
-function meetingStatus(meeting: Meeting, focusKey: number | undefined, now: Date) {
-  if (meeting.meeting_key === focusKey) return 'focus'
-  if (meetingHasStarted(meeting, now)) return 'past'
-  return 'future'
-}
-
-function pickAnalysisSession(weekend: Weekend | undefined): WeekendSession | undefined {
-  if (!weekend) return undefined
-  const local = weekend.sessions.filter((s) => s.source === 'local')
-  const partial = weekend.sessions.filter((s) => s.source === 'partial')
-  const pool = local.length > 0 ? local : partial.length > 0 ? partial : weekend.sessions
-  const race = pool.find((s) => s.session.session_type?.toLowerCase().includes('race'))
-  if (race) return race
-  const qual = pool.find((s) => s.session.session_type?.toLowerCase().includes('qualifying'))
-  if (qual) return qual
-  return pool[0]
-}
-
-export function CommandCenterPage() {
-  const [now, setNow] = useState(() => Date.now())
-
-  const seasonsQuery = useQuery({
-    queryKey: ['seasons'],
-    queryFn: fetchSeasons,
-  })
-
-  const latestSeason = seasonsQuery.data?.[0] ?? null
-
-  const meetingsQuery = useQuery({
-    queryKey: ['meetings', latestSeason],
-    queryFn: () => fetchLocalMeetings(latestSeason!),
-    enabled: latestSeason != null,
-  })
-
-  const seasonMeetingsQuery = useQuery({
-    queryKey: ['season-meetings', latestSeason],
-    queryFn: () => fetchSeasonMeetings(latestSeason!),
-    enabled: latestSeason != null,
-  })
-
-  const localMeetings = meetingsQuery.data ?? []
-  const seasonMeetings = seasonMeetingsQuery.data?.length ? seasonMeetingsQuery.data : localMeetings
-  const focusMeetings = seasonMeetings.length > 0 ? seasonMeetings : localMeetings
-
-  const weekendQueries = useQueries({
-    queries: localMeetings.map((meeting) => ({
-      queryKey: ['weekend', meeting.meeting_key],
-      queryFn: () => fetchWeekend(meeting.meeting_key),
-      enabled: localMeetings.length > 0,
-      staleTime: 60_000,
-    })),
-  })
-
-  const liveQuery = useQuery({
-    queryKey: ['live-state'],
-    queryFn: fetchLiveState,
-    staleTime: 5_000,
-  })
-
-  const championshipQuery = useQuery({
-    queryKey: ['championship-hub', latestSeason],
-    queryFn: () => fetchChampionshipHub(latestSeason!),
-    enabled: latestSeason != null,
-  })
-  const champHub = championshipQuery.data
-
-  useEffect(() => {
-    const timer = window.setInterval(() => setNow(Date.now()), 1000)
-    return () => window.clearInterval(timer)
-  }, [])
-
-  const nowDate = useMemo(() => new Date(now), [now])
-
-  const weekendsByKey = useMemo(() => {
-    const map = new Map<number, Weekend>()
-    localMeetings.forEach((meeting, i) => {
-      const data = weekendQueries[i]?.data
-      if (data) map.set(meeting.meeting_key, data)
-    })
-    return map
-  }, [localMeetings, weekendQueries])
-
-  const weekendList = useMemo(() => weekendQueries.map((q) => q.data), [weekendQueries])
-  const meetingStats = countWeekendStats(weekendList)
-  const focusMeeting = pickFocusMeeting(focusMeetings, nowDate)
-  const focusWeekend = focusMeeting ? weekendsByKey.get(focusMeeting.meeting_key) : undefined
-  const openF1SessionsQuery = useQuery({
-    queryKey: ['sessions', focusMeeting?.meeting_key, 'openf1'],
-    queryFn: () => fetchSessions(focusMeeting!.meeting_key, 'openf1'),
-    enabled: focusMeeting != null && focusWeekend == null,
-    staleTime: 60_000,
-  })
-  const openF1WeekendSessions: WeekendSession[] = useMemo(
-    () =>
-      (openF1SessionsQuery.data ?? []).map((session) => ({
-        session,
-        source: 'none',
-        datasets: missingDatasets,
-      })),
-    [openF1SessionsQuery.data],
-  )
-  const focusWeekendSessions = focusWeekend?.sessions ?? openF1WeekendSessions
-  const focusKind = focusMeeting ? focusMeetingKind(focusMeeting, nowDate) : null
-  const focusSessions: Session[] = sortSessionsByStart(focusWeekendSessions.map((s) => s.session))
-  const { current: currentSession, next: nextSession } = currentAndNextSession(focusSessions, nowDate)
-
-  const analysisSession = pickAnalysisSession(focusWeekend)
-  const actionSession =
-    analysisSession?.session ??
-    currentSession ??
-    nextSession ??
-    focusWeekendSessions.find((s) => s.session.session_key === focusWeekend?.default_session_key)?.session ??
-    focusWeekendSessions[0]?.session
-  const analysisSessionKey = actionSession?.session_key
-
-  const liveActive = liveQuery.data?.is_live === true
-  const heroStateKind = heroState({
-    now: nowDate,
-    liveActive,
-    currentSession,
-    focusKind,
-  })
-
-  const lastPastMeeting = useMemo(
-    () => mostRecentPastMeeting(focusMeetings, nowDate),
-    [focusMeetings, nowDate],
-  )
-  const lastPastWeekend = lastPastMeeting ? weekendsByKey.get(lastPastMeeting.meeting_key) : undefined
-  const lastRaceAnalysis = pickAnalysisSession(lastPastWeekend)
-  const lastRaceSessionKey = lastRaceAnalysis?.session.session_key
-
-  const lastRaceHubQuery = useQuery({
-    queryKey: ['race-hub', lastRaceSessionKey, 'hero-podium'],
-    queryFn: () => fetchRaceHub(lastRaceSessionKey!),
-    enabled: lastRaceSessionKey != null && heroStateKind === 'between',
-    staleTime: 60_000,
-  })
-
-  const nextMeetingForHero = useMemo(() => {
-    if (heroStateKind !== 'between') return null
-    return nextUpcomingMeeting(focusMeetings, nowDate)
-  }, [heroStateKind, focusMeetings, nowDate])
-
-  const lastRacePodium = lastRaceHubQuery.data?.results ?? []
-  const lastRaceName = champHub?.last_race ?? lastPastMeeting?.meeting_name ?? ''
-
-  if (seasonsQuery.isLoading) {
-    return <div className="page loading-state">loading command center…</div>
-  }
-
-  if (seasonsQuery.isError) {
-    return (
-      <div className="page error-box">
-        {seasonsQuery.error instanceof Error ? seasonsQuery.error.message : 'Failed to load seasons'}
-      </div>
-    )
-  }
-
-  const seasons = seasonsQuery.data ?? []
-
-  if (seasons.length === 0) {
-    return (
-      <div className="cc-page cc-empty" data-testid="command-center-empty">
-        <div className="cc-empty-band">
-          <span className="cc-empty-eyebrow mono">box-box · command center</span>
-          <h1 className="cc-empty-title">No local data yet</h1>
-          <p className="cc-empty-sub">
-            Ingest a race weekend from the CLI to populate this screen with live status, next-session
-            countdowns, and analysis links.
-          </p>
-        </div>
-        <div className="cc-empty-actions">
-          <Link to="/live" className="cc-action cc-action-live">
-            <span className="cc-action-label">Live Timing</span>
-            <span className="cc-action-meta">Standby</span>
-          </Link>
-          <Link to="/admin" className="cc-action">
-            <span className="cc-action-label">Admin · Data Health</span>
-            <span className="cc-action-meta">Ingestion guidance</span>
-          </Link>
-        </div>
-      </div>
-    )
-  }
-
-  const accent = countryAccent(focusMeeting ?? null)
-  const accentStyle = { '--gp-accent': accent } as React.CSSProperties
-
-  return (
-    <div className="cc-page" data-testid="command-center" style={accentStyle}>
-      <div className="cc-topbar">
-        <span className="cc-topbar-label mono">box-box · command center</span>
-        <span className="cc-topbar-meta mono">
-          {latestSeason} season · {meetingStats.full}/{meetingStats.total || 0} weekends full
-        </span>
-        <span className="cc-live-pill" data-testid="cc-live-status">
-          <span className={`cc-live-dot ${liveActive ? 'live' : ''}`} />
-          {liveActive ? 'Live session active' : 'No live session'}
-        </span>
-      </div>
-
-      {!focusMeeting && (
-        <div className="missing-notice">
-          No meetings ingested for {latestSeason}. Run{' '}
-          <code>box-box --ingest-year {latestSeason}</code>
-        </div>
-      )}
-
-      {focusMeeting && focusKind && (
-        <CommandCenterHero
-          state={heroStateKind}
-          now={nowDate}
-          accent={accent}
-          liveActive={liveActive}
-          liveData={liveQuery.data?.data}
-          focusMeeting={focusMeeting}
-          focusKind={focusKind}
-          sessions={focusWeekendSessions}
-          currentSession={currentSession}
-          nextSession={nextSession}
-          analysisSessionKey={analysisSessionKey}
-          analysisSessionName={actionSession?.session_name}
-          lastRaceName={lastRaceName}
-          lastRacePodium={lastRacePodium}
-          lastRaceSessionKey={lastRaceSessionKey}
-          nextMeeting={nextMeetingForHero}
-        />
-      )}
-
-      <div className="cc-dashboard-grid">
-        <div className="cc-dashboard-main">
-          <div 
-            className="cc-ambient-aura" 
-            aria-hidden="true" 
-            style={focusMeeting ? { '--aura-accent': countryAccent(focusMeeting) } as React.CSSProperties : undefined} 
-          />
-          <div className="cc-dashboard-panel">
-            {seasonMeetings.length > 0 && (
-              <section className="cc-season-calendar" data-testid="cc-season-calendar">
-              <div className="sec-header">
-                <span className="sec-title">Season Calendar</span>
-                <span className="sec-meta mono">
-                  {seasonMeetings.length} rounds · {meetingStats.full}/{meetingStats.total || 0} local
-                </span>
-              </div>
-              <div className="cc-calendar-grid" role="list">
-                {seasonMeetings.map((meeting, index) => {
-                  const weekend = weekendsByKey.get(meeting.meeting_key)
-                  const target = pickAnalysisSession(weekend)
-                  const targetKey = target?.session.session_key ?? weekend?.default_session_key
-                  const status = meetingStatus(meeting, focusMeeting?.meeting_key, nowDate)
-                  const cardAccent = countryAccent(meeting)
-                  return (
-                    <Link
-                      key={meeting.meeting_key}
-                      to="/race-hub"
-                      search={targetKey ? { session_key: targetKey } : {}}
-                      className={`cc-calendar-card cc-calendar-${status}`}
-                      data-testid={`cc-calendar-${meeting.meeting_key}`}
-                      role="listitem"
-                      style={{ '--gp-card-accent': cardAccent } as React.CSSProperties}
-                    >
-                      <div className="cc-calendar-accent" aria-hidden="true" />
-                      <div className="cc-calendar-top mono">
-                        <span className="cc-calendar-round">R{String(index + 1).padStart(2, '0')}</span>
-                        <span className={`cc-cov-dot cc-cov-${weekend?.source ?? 'none'}`} aria-hidden="true" />
-                      </div>
-                      <div className="cc-calendar-id">
-                        {countryFlag(meeting) && <span className="cc-calendar-flag">{countryFlag(meeting)}</span>}
-                      </div>
-                      <span className="cc-calendar-decal mono">{countryDecal(meeting)}</span>
-                      <div className="cc-calendar-copy">
-                        <div className="cc-calendar-name">{meeting.meeting_name}</div>
-                        <div className="cc-calendar-circuit mono">{meeting.circuit_short_name || meeting.location}</div>
-                        <div className="cc-calendar-date mono">{formatGpDateRange(meeting)}</div>
-                      </div>
-                    </Link>
-                  )
-                })}
-              </div>
-              {seasonMeetingsQuery.isError && (
-                <div className="cc-side-empty">Using local meetings because the full calendar could not load.</div>
-              )}
-            </section>
-            )}
-          </div>
-        </div>
-
-        <div className="cc-dashboard-sidebar">
-          {champHub && (
-            <section className="cc-champ-snapshot glass-panel" data-testid="cc-champ-snapshot" style={{ padding: 'var(--s5)', borderRadius: '12px' }}>
-              <div className="cc-champ-header">
-                <span>Championship Leaders</span>
-                <Link to="/championship" className="cc-champ-link">Full Standings →</Link>
-              </div>
-              <div className="cc-champ-group-label">Drivers</div>
-              <div className="cc-champ-list">
-                {champHub.drivers.slice(0, 3).map((d) => (
-                  <div key={d.driver_number} className="cc-champ-row">
-                    <div className="cc-champ-left">
-                      <div className="cc-champ-color" style={{ color: `#${d.team_colour}`, background: 'currentColor' }} />
-                      <span className="cc-champ-name">{d.name_acronym}</span>
-                    </div>
-                    <div className="cc-champ-form" title="Last 5 races">
-                      <FormSparkline form={d.form} color={`#${d.team_colour}`} />
-                    </div>
-                    <div className="cc-champ-right">
-                      <span className="cc-champ-gap">
-                        {d.position === 1 ? '—' : `-${champHub.drivers[0].points - d.points}`}
-                      </span>
-                      <span className="cc-champ-pts">{d.points}</span>
-                    </div>
-                  </div>
-                ))}
-              </div>
-              <div className="cc-champ-group-label">Constructors</div>
-              <div className="cc-champ-list">
-                {champHub.teams.slice(0, 3).map((t, i) => (
-                  <div key={t.team_name} className="cc-champ-row">
-                    <div className="cc-champ-left">
-                      <div className="cc-champ-color" style={{ color: `#${t.team_colour}`, background: 'currentColor' }} />
-                      <span className="cc-champ-name">{t.team_name}</span>
-                    </div>
-                    <div className="cc-champ-form" style={{ opacity: 0.4, fontSize: '11px', display: 'flex', gap: '4px', alignItems: 'center' }} title={`${t.wins} Wins`}>
-                      <Trophy size={12} /> {t.wins}
-                    </div>
-                    <div className="cc-champ-right">
-                      <span className="cc-champ-gap">
-                        {i === 0 ? '—' : `-${champHub.teams[0].points - t.points}`}
-                      </span>
-                      <span className="cc-champ-pts">{t.points}</span>
-                    </div>
-                  </div>
-                ))}
-              </div>
-            </section>
-          )}
-
-          {focusWeekendSessions.length > 0 && (
-            <section className="cc-schedule" data-testid="cc-schedule">
-              <div className="sec-header">
-                <span className="sec-title">Weekend Schedule</span>
-                <span className="sec-meta mono">{focusWeekendSessions.length} sessions</span>
-              </div>
-              <div className="cc-session-strip" role="list">
-                {focusWeekendSessions.map(({ session, source, datasets }) => {
-                  const status = classifySessionStatus(session, nowDate)
-                  const isNext = nextSession?.session_key === session.session_key
-                  const isCurrent = currentSession?.session_key === session.session_key
-                  const isLive = isCurrent && liveActive
-                  return (
-                    <Link
-                      key={session.session_key}
-                      to="/race-hub"
-                      search={{ session_key: session.session_key }}
-                      className={`cc-session-card ui-card interactive cc-status-${status}${isNext ? ' is-next' : ''}${
-                        isLive ? ' is-live glass-panel' : ''
-                      }`}
-                      data-testid={`cc-session-${session.session_key}`}
-                      role="listitem"
-                    >
-                      <div className="cc-session-card-head">
-                        <span className="cc-session-abbrev mono">
-                          {sessionTypeAbbrev(session.session_type, session.session_name)}
-                        </span>
-                        <span className={`cc-session-status cc-status-pill-${status}`}>
-                          {isCurrent ? 'On track' : status === 'done' ? 'Done' : isNext ? 'Next' : 'Upcoming'}
-                        </span>
-                      </div>
-                      <div className="cc-session-name">{session.session_name}</div>
-                      <div className="cc-session-time mono">{formatSessionScheduleTime(session.date_start)}</div>
-                      <div className="cc-session-cov mono">
-                        <span className={`cc-cov-dot cc-cov-${source}`} aria-hidden="true" />
-                        {formatCoverageHint(datasets)}
-                      </div>
-                    </Link>
-                  )
-                })}
-              </div>
-            </section>
-          )}
-
-          <PaddockBriefing />
-        </div>
-      </div>
-    </div>
-  )
-}
-
-function FormSparkline({ form, color }: { form: number[], color: string }) {
-  if (!form || form.length === 0) return null
-  const max = Math.max(...form, 26) // 26 is standard max for a race win
-  const width = 45
-  const height = 14
-  const step = width / Math.max(form.length - 1, 1)
-
-  const points = form.map((val, i) => {
-    const x = i * step
-    const y = height - (val / max) * height
-    return `${x},${y}`
-  }).join(' ')
-
-  return (
-    <svg width={width} height={height} style={{ overflow: 'visible' }}>
-      <polyline
-        fill="none"
-        stroke={color}
-        strokeWidth="1.5"
-        strokeLinecap="round"
-        strokeLinejoin="round"
-        points={points}
-      />
-    </svg>
-  )
-}
-

frontend/src/pages/DriverProfilePage.tsx

@@ -0,0 +1,369 @@
+import { useQuery } from '@tanstack/react-query'
+import { Link } from '@tanstack/react-router'
+import { fetchDriverSummary, fetchSeasons } from '../api'
+import { teamColor } from '../utils'
+import { countryFlag } from '../lib/gpIdentity'
+import {
+  formatDelta,
+  formatPosition,
+  gridFinishDeltas,
+  type RoundDelta,
+} from '../lib/driverProfile'
+import type { DriverSummary } from '../types'
+import '../styles/driver-profile.css'
+
+interface Props {
+  driverNumber: number
+  year?: number
+}
+
+function fmtPts(n: number): string {
+  return Number.isInteger(n) ? String(n) : n.toFixed(1)
+}
+
+export function DriverProfilePage({ driverNumber, year }: Props) {
+  // Without an explicit ?year=, default to the latest ingested season; if the
+  // seasons list is empty/unavailable the backend falls back to the current year.
+  const seasonsQuery = useQuery({
+    queryKey: ['seasons'],
+    queryFn: fetchSeasons,
+    enabled: year == null,
+  })
+  const resolvedYear = year ?? seasonsQuery.data?.[0]
+  const seasonsSettled = year != null || !seasonsQuery.isLoading
+
+  const summaryQuery = useQuery({
+    queryKey: ['driver-summary', driverNumber, resolvedYear ?? 'latest'],
+    queryFn: () => fetchDriverSummary(driverNumber, resolvedYear),
+    enabled: seasonsSettled && driverNumber > 0,
+    staleTime: 5 * 60_000,
+  })
+
+  if (driverNumber <= 0) {
+    return <div className="page error-box">Invalid driver number</div>
+  }
+  if (!seasonsSettled || summaryQuery.isLoading) {
+    return <div className="page loading-state">loading driver profile…</div>
+  }
+  if (summaryQuery.isError) {
+    return (
+      <div className="page error-box">
+        {summaryQuery.error instanceof Error
+          ? summaryQuery.error.message
+          : 'Failed to load driver profile'}
+      </div>
+    )
+  }
+  const summary = summaryQuery.data
+  if (!summary) {
+    return <div className="page error-box">No driver data</div>
+  }
+  return <DriverProfileBody summary={summary} />
+}
+
+function DriverProfileBody({ summary }: { summary: DriverSummary }) {
+  const color = teamColor(summary.team_colour)
+  const deltas = gridFinishDeltas(summary.rounds)
+
+  return (
+    <div className="dp-page" data-testid="driver-profile">
+      <header className="dp-header" data-testid="dp-header" style={{ borderLeftColor: color }}>
+        <div className="dp-identity">
+          <div className="dp-title-row">
+            <span className="dp-code mono">{summary.name_acronym || `#${summary.driver_number}`}</span>
+            <span className="dp-num mono" style={{ color }}>
+              #{summary.driver_number}
+            </span>
+          </div>
+          <h1 className="dp-name">{summary.full_name || `Driver ${summary.driver_number}`}</h1>
+          <div className="dp-team">
+            <span className="dp-team-swatch" style={{ background: color }} />
+            {summary.team_name || 'Unknown team'}
+            <span className="dp-season mono">{summary.season}</span>
+          </div>
+        </div>
+        <div className="dp-stat-rail">
+          <div className="dp-stat">
+            <div className="dp-stat-value mono">{summary.position > 0 ? `P${summary.position}` : '—'}</div>
+            <div className="dp-stat-label">Championship</div>
+          </div>
+          <div className="dp-stat">
+            <div className="dp-stat-value mono">{fmtPts(summary.points)}</div>
+            <div className="dp-stat-label">Points</div>
+          </div>
+          <div className="dp-stat">
+            <div className="dp-stat-value mono">{summary.wins}</div>
+            <div className="dp-stat-label">Wins</div>
+          </div>
+          <div className="dp-stat">
+            <div className="dp-stat-value mono">{summary.podiums}</div>
+            <div className="dp-stat-label">Podiums</div>
+          </div>
+          <div className="dp-stat">
+            <div className="dp-stat-value mono">{summary.poles}</div>
+            <div className="dp-stat-label">Poles</div>
+          </div>
+        </div>
+        <Link to="/championship" className="dp-back mono">
+          ← Championship
+        </Link>
+      </header>
+
+      <section className="dp-section" data-testid="dp-form">
+        <h2 className="dp-section-title mono">Season form</h2>
+        {summary.cumulative.length > 0 ? (
+          <div className="dp-form-grid">
+            <CumulativeLine
+              cumulative={summary.cumulative}
+              labels={summary.round_labels}
+              color={color}
+            />
+            <FormStrip form={summary.form} color={color} />
+          </div>
+        ) : (
+          <div className="dp-empty">No completed rounds yet.</div>
+        )}
+      </section>
+
+      <section className="dp-section" data-testid="dp-quali-race">
+        <h2 className="dp-section-title mono">Quali vs race</h2>
+        {deltas.some((d) => d.delta != null) ? (
+          <GridVsRaceChart deltas={deltas} color={color} />
+        ) : (
+          <div className="dp-empty">No grid-vs-finish data yet.</div>
+        )}
+      </section>
+
+      <section className="dp-section" data-testid="dp-rounds">
+        <h2 className="dp-section-title mono">Track by track</h2>
+        {summary.rounds.length > 0 ? (
+          <RoundsTable summary={summary} deltas={deltas} />
+        ) : (
+          <div className="dp-empty">No completed rounds yet.</div>
+        )}
+      </section>
+    </div>
+  )
+}
+
+const LINE_W = 640
+const LINE_H = 180
+const LINE_PL = 44
+const LINE_PR = 16
+const LINE_PT = 12
+const LINE_PB = 24
+
+function CumulativeLine({
+  cumulative,
+  labels,
+  color,
+}: {
+  cumulative: number[]
+  labels: string[]
+  color: string
+}) {
+  const n = cumulative.length
+  const maxY = Math.max(25, ...cumulative)
+  const plotW = LINE_W - LINE_PL - LINE_PR
+  const plotH = LINE_H - LINE_PT - LINE_PB
+  const x = (i: number) => (n <= 1 ? LINE_PL + plotW / 2 : LINE_PL + (i * plotW) / (n - 1))
+  const y = (v: number) => LINE_PT + plotH - (v / maxY) * plotH
+  const points = cumulative.map((v, i) => `${x(i).toFixed(1)},${y(v).toFixed(1)}`).join(' ')
+
+  const tickStep = Math.max(1, Math.ceil(n / 8))
+  const ticks: { x: number; label: string }[] = []
+  for (let i = 0; i < n; i += tickStep) {
+    ticks.push({ x: x(i), label: labels[i] ?? `R${i + 1}` })
+  }
+
+  return (
+    <figure className="dp-chart">
+      <figcaption className="dp-chart-caption mono">Cumulative points</figcaption>
+      <svg viewBox={`0 0 ${LINE_W} ${LINE_H}`} className="dp-chart-svg" role="img" aria-label="Cumulative points per round">
+        {[0, 0.5, 1].map((f) => {
+          const v = Math.round(maxY * f)
+          return (
+            <g key={f}>
+              <line x1={LINE_PL} y1={y(v)} x2={LINE_W - LINE_PR} y2={y(v)} className="dp-gridline" />
+              <text x={LINE_PL - 6} y={y(v) + 3} textAnchor="end" className="dp-axis">
+                {v}
+              </text>
+            </g>
+          )
+        })}
+        {ticks.map((t) => (
+          <text key={t.label} x={t.x} y={LINE_H - 8} textAnchor="middle" className="dp-axis">
+            {t.label}
+          </text>
+        ))}
+        <polyline
+          points={points}
+          fill="none"
+          stroke={color}
+          strokeWidth="2.2"
+          strokeLinejoin="round"
+          strokeLinecap="round"
+        />
+        <circle cx={x(n - 1)} cy={y(cumulative[n - 1])} r="3.2" fill={color} />
+      </svg>
+    </figure>
+  )
+}
+
+function FormStrip({ form, color }: { form: number[]; color: string }) {
+  const max = Math.max(25, ...form)
+  return (
+    <div className="dp-form-strip">
+      <div className="dp-chart-caption mono">Last {form.length} races</div>
+      <div className="dp-form-bars">
+        {form.map((pts, i) => (
+          <div className="dp-form-bar" key={i} title={`${fmtPts(pts)} pts`}>
+            <div
+              className="dp-form-bar-fill"
+              style={{ height: `${Math.max(4, (pts / max) * 100)}%`, background: color }}
+            />
+            <span className="dp-form-bar-val mono">{fmtPts(pts)}</span>
+          </div>
+        ))}
+      </div>
+    </div>
+  )
+}
+
+const DELTA_H = 190
+const DELTA_PT = 14
+const DELTA_PB = 30
+
+function GridVsRaceChart({ deltas, color }: { deltas: RoundDelta[]; color: string }) {
+  const maxAbs = Math.max(1, ...deltas.map((d) => Math.abs(d.delta ?? 0)))
+  const colW = 34
+  const w = Math.max(240, deltas.length * colW)
+  const plotH = DELTA_H - DELTA_PT - DELTA_PB
+  const zeroY = DELTA_PT + plotH / 2
+  const scale = plotH / 2 / maxAbs
+
+  return (
+    <figure className="dp-chart">
+      <figcaption className="dp-chart-caption mono">
+        Positions gained (▲) / lost (▼) from grid to flag, per round
+      </figcaption>
+      <div className="dp-chart-scroll">
+        <svg
+          viewBox={`0 0 ${w} ${DELTA_H}`}
+          width={w}
+          height={DELTA_H}
+          className="dp-delta-svg"
+          role="img"
+          aria-label="Positions gained or lost per round"
+        >
+          <line x1={0} y1={zeroY} x2={w} y2={zeroY} className="dp-zeroline" />
+          {deltas.map((d, i) => {
+            const cx = i * colW + colW / 2
+            if (d.delta == null) {
+              return (
+                <g key={d.round}>
+                  <text x={cx} y={zeroY - 6} textAnchor="middle" className="dp-axis">
+                    ·
+                  </text>
+                  <text x={cx} y={DELTA_H - 8} textAnchor="middle" className="dp-axis">
+                    R{d.round}
+                  </text>
+                </g>
+              )
+            }
+            const h = Math.abs(d.delta) * scale
+            const yTop = d.delta >= 0 ? zeroY - h : zeroY
+            return (
+              <g key={d.round}>
+                <title>{`${d.label}: ${formatPosition(d.grid)} → ${formatPosition(d.finish)} (${formatDelta(d.delta)})`}</title>
+                <rect
+                  x={cx - 8}
+                  y={yTop}
+                  width={16}
+                  height={Math.max(1.5, h)}
+                  rx={2}
+                  fill={color}
+                  opacity={d.delta >= 0 ? 0.95 : 0.45}
+                />
+                <text
+                  x={cx}
+                  y={d.delta >= 0 ? yTop - 4 : yTop + h + 11}
+                  textAnchor="middle"
+                  className="dp-delta-val mono"
+                >
+                  {formatDelta(d.delta)}
+                </text>
+                <text x={cx} y={DELTA_H - 8} textAnchor="middle" className="dp-axis">
+                  R{d.round}
+                </text>
+              </g>
+            )
+          })}
+        </svg>
+      </div>
+    </figure>
+  )
+}
+
+function statusNote(d: RoundDelta): string {
+  if (d.status === 'dnf') return 'DNF'
+  if (d.status === 'dns') return 'DNS'
+  if (d.status === 'dsq') return 'DSQ'
+  if (d.status === 'absent') return '—'
+  return ''
+}
+
+function RoundsTable({ summary, deltas }: { summary: DriverSummary; deltas: RoundDelta[] }) {
+  return (
+    <div className="dp-scroll">
+      <table className="dp-table">
+        <thead>
+          <tr>
+            <th className="l">Rnd</th>
+            <th className="l">Grand Prix</th>
+            <th className="r">Grid</th>
+            <th className="r">Race</th>
+            <th className="r">Δ</th>
+            <th className="r">Pts</th>
+            <th className="l"></th>
+          </tr>
+        </thead>
+        <tbody>
+          {summary.rounds.map((r, i) => {
+            const d = deltas[i]
+            return (
+              <tr key={r.meeting_key}>
+                <td className="mono dp-td-dim">R{i + 1}</td>
+                <td>
+                  <span className="dp-flag" aria-hidden="true">
+                    {countryFlag({ country_code: r.country_code, country_flag: '' })}
+                  </span>
+                  {r.meeting_name}
+                </td>
+                <td className="r mono">{formatPosition(d.grid)}</td>
+                <td className="r mono">{formatPosition(d.finish)}</td>
+                <td
+                  className="r mono"
+                  style={{
+                    color:
+                      d.delta == null
+                        ? 'var(--text-3)'
+                        : d.delta > 0
+                          ? 'var(--green)'
+                          : d.delta < 0
+                            ? 'var(--red)'
+                            : 'var(--text-2)',
+                  }}
+                >
+                  {formatDelta(d.delta)}
+                </td>
+                <td className="r mono">{fmtPts(r.points)}</td>
+                <td className="dp-td-dim mono">{statusNote(d)}</td>
+              </tr>
+            )
+          })}
+        </tbody>
+      </table>
+    </div>
+  )
+}

frontend/src/pages/ExplorePage.tsx

@@ -0,0 +1,156 @@
+import { useMemo } from 'react'
+import { useQueries, useQuery } from '@tanstack/react-query'
+import { Link } from '@tanstack/react-router'
+import {
+  fetchChampionshipHub,
+  fetchLocalMeetings,
+  fetchSeasonMeetings,
+  fetchSeasons,
+  fetchWeekend,
+} from '../api'
+import { countryFlag, formatGpDateRange } from '../lib/gpIdentity'
+import { meetingHasStarted } from '../lib/schedule'
+import { teamColor } from '../utils'
+import type { Weekend } from '../types'
+import '../styles/weekend.css'
+
+function analysisKey(weekend: Weekend | undefined): number | undefined {
+  if (!weekend) return undefined
+  const race = weekend.sessions.find((s) => s.session.session_type?.toLowerCase().includes('race'))
+  return race?.session.session_key ?? weekend.default_session_key
+}
+
+export function ExplorePage() {
+  const now = useMemo(() => new Date(), [])
+
+  const seasonsQuery = useQuery({ queryKey: ['seasons'], queryFn: fetchSeasons })
+  const season = seasonsQuery.data?.[0] ?? null
+
+  const localMeetingsQuery = useQuery({
+    queryKey: ['meetings', season, 'local'],
+    queryFn: () => fetchLocalMeetings(season!),
+    enabled: season != null,
+  })
+  const seasonMeetingsQuery = useQuery({
+    queryKey: ['season-meetings', season],
+    queryFn: () => fetchSeasonMeetings(season!),
+    enabled: season != null,
+  })
+  const championshipQuery = useQuery({
+    queryKey: ['championship-hub', season],
+    queryFn: () => fetchChampionshipHub(season!),
+    enabled: season != null,
+  })
+
+  const localMeetings = localMeetingsQuery.data ?? []
+  const meetings = seasonMeetingsQuery.data?.length ? seasonMeetingsQuery.data : localMeetings
+
+  const weekendQueries = useQueries({
+    queries: localMeetings.map((m) => ({
+      queryKey: ['weekend', m.meeting_key],
+      queryFn: () => fetchWeekend(m.meeting_key),
+      enabled: localMeetings.length > 0,
+      staleTime: 60_000,
+    })),
+  })
+  const weekendsByKey = useMemo(() => {
+    const map = new Map<number, Weekend>()
+    localMeetings.forEach((m, i) => {
+      const data = weekendQueries[i]?.data
+      if (data) map.set(m.meeting_key, data)
+    })
+    return map
+  }, [localMeetings, weekendQueries])
+
+  const drivers = championshipQuery.data?.drivers ?? []
+  const activeMeetings = meetings.filter((m) => !m.is_cancelled)
+
+  if (seasonsQuery.isLoading) {
+    return <div className="wk-status" data-testid="explore-loading"><p className="wk-status-title">Loading…</p></div>
+  }
+
+  return (
+    <main className="wk-page wk-explore" data-testid="explore-page">
+      <div className="wk-eyebrow mono">Explore · {season ?? 'season'}</div>
+
+      <section className="wk-explore-section" aria-labelledby="explore-calendar-title">
+        <header className="wk-card-head">
+          <span className="wk-card-title" id="explore-calendar-title">Season races</span>
+          <span className="wk-card-link mono">{activeMeetings.length} rounds</span>
+        </header>
+        {activeMeetings.length === 0 ? (
+          <p className="wk-status-sub" data-testid="explore-calendar-empty">No season calendar available yet.</p>
+        ) : (
+          <ol className="wk-explore-grid" role="list">
+            {activeMeetings.map((meeting, index) => {
+              const weekend = weekendsByKey.get(meeting.meeting_key)
+              const target = analysisKey(weekend)
+              const done = meetingHasStarted(meeting, now)
+              const card = (
+                <>
+                  <div className="wk-explore-top mono">
+                    <span>R{String(index + 1).padStart(2, '0')}</span>
+                    <span className="wk-explore-flag">
+                      {countryFlag(meeting) || meeting.country_code}
+                    </span>
+                  </div>
+                  <div className="wk-explore-name">{meeting.meeting_name}</div>
+                  <div className="wk-explore-meta mono">{meeting.circuit_short_name || meeting.location}</div>
+                  <div className="wk-explore-meta mono">{formatGpDateRange(meeting)}</div>
+                  <span className={`wk-explore-state ${done ? 'is-done' : 'is-upcoming'}`}>
+                    {done ? 'Completed' : 'Upcoming'}
+                  </span>
+                </>
+              )
+              return (
+                <li key={meeting.meeting_key} className="wk-explore-item" role="listitem">
+                  {target ? (
+                    <Link
+                      to="/race-hub"
+                      search={{ session_key: target }}
+                      className="wk-explore-card is-link"
+                      data-testid={`explore-race-${meeting.meeting_key}`}
+                    >
+                      {card}
+                    </Link>
+                  ) : (
+                    <div className="wk-explore-card" data-testid={`explore-race-${meeting.meeting_key}`}>{card}</div>
+                  )}
+                </li>
+              )
+            })}
+          </ol>
+        )}
+      </section>
+
+      <section className="wk-explore-section" aria-labelledby="explore-drivers-title">
+        <header className="wk-card-head">
+          <span className="wk-card-title" id="explore-drivers-title">Drivers</span>
+          <Link to="/championship" className="wk-card-link">Championship →</Link>
+        </header>
+        {drivers.length === 0 ? (
+          <p className="wk-status-sub" data-testid="explore-drivers-empty">Driver data not available yet.</p>
+        ) : (
+          <ol className="wk-explore-drivers" role="list">
+            {drivers.map((d) => (
+              <li key={d.driver_number} role="listitem">
+                <Link
+                  to="/drivers/$driverNumber"
+                  params={{ driverNumber: String(d.driver_number) }}
+                  search={season ? { year: season } : {}}
+                  className="wk-driver-chip"
+                  style={{ ['--wk-team' as string]: teamColor(d.team_colour) }}
+                  data-testid={`explore-driver-${d.driver_number}`}
+                >
+                  <span className="wk-driver-pos mono">{d.position}</span>
+                  <span className="wk-driver-code">{d.name_acronym}</span>
+                  <span className="wk-driver-pts mono">{d.points}</span>
+                </Link>
+              </li>
+            ))}
+          </ol>
+        )}
+      </section>
+    </main>
+  )
+}

frontend/src/pages/RaceHubPage.tsx

@@ -1,12 +1,8 @@
-import { useEffect, useMemo, useState } from 'react'
+import { useEffect, useState } from 'react'
 import { useQuery } from '@tanstack/react-query'
-import { useNavigate } from '@tanstack/react-router'
+import { Link, useNavigate } from '@tanstack/react-router'
-import {
+import { fetchRaceHub, fetchWeekend, fetchWeekendContext } from '../api'
-  fetchLocalMeetings,
+import { weekendFocusSearch } from '../lib/routeSearch'
-  fetchRaceHub,
-  fetchSeasons,
-  fetchWeekend,
-} from '../api'
 import { DatasetStrip } from '../components/DatasetStrip'
 import { RaceStoryCanvas } from '../components/RaceStoryCanvas'
 import { TabBar, type Tab } from '../components/TabBar'
@@ -17,77 +13,64 @@ import { CompareView } from '../components/CompareView'
 import { RaceControlView } from '../components/RaceControlView'
 import { WeatherView } from '../components/WeatherView'
 import { OverviewView } from '../components/OverviewView'
+import {
+  PartialAnalysisBanner,
+  PreSessionView,
+  SessionPhaseView,
+} from '../components/PreSessionView'
 import { WeekendSwitcher } from '../components/WeekendSwitcher'
 import { SourceBadge } from '../components/SourceBadge'
 import { countryAccent, countryDecal, formatGpDateRange } from '../lib/gpIdentity'
-import { formatCoverageHint, sessionTypeAbbrev } from '../lib/coverage'
+import { sessionTypeAbbrev } from '../lib/coverage'
+import { formatSessionScheduleTime, sortSessionsByStart } from '../lib/schedule'
 import {
-  formatSessionScheduleTime,
+  defaultAnalysisSessionKey,
-  pickFocusMeeting,
+  isPartialAnalysis,
-  sortSessionsByStart,
+  isPreSession,
-} from '../lib/schedule'
+  isPreparing,
-import type { Weekend, WeekendSession } from '../types'
+  isUnavailable,
+  resolveSessionState,
+  sessionStateDotClass,
+  sessionStateLabel,
+} from '../lib/sessionState'
+import type { WeekendSession } from '../types'
 
 interface Props {
   sessionKey: number
 }
 
-function pickAnalysisSession(weekend: Weekend | undefined): WeekendSession | undefined {
-  if (!weekend) return undefined
-  const local = weekend.sessions.filter((s) => s.source === 'local')
-  const partial = weekend.sessions.filter((s) => s.source === 'partial')
-  const pool = local.length > 0 ? local : partial.length > 0 ? partial : weekend.sessions
-  const race = pool.find((s) => s.session.session_type?.toLowerCase().includes('race'))
-  if (race) return race
-  const qual = pool.find((s) => s.session.session_type?.toLowerCase().includes('qualifying'))
-  if (qual) return qual
-  return pool[0]
-}
-
 export function RaceHubPage({ sessionKey }: Props) {
   const navigate = useNavigate()
   const [activeTab, setActiveTab] = useState<Tab>('overview')
   const [switcherOpen, setSwitcherOpen] = useState(false)
+  const [showDiagnostics, setShowDiagnostics] = useState(false)
+  const [phaseDiagnostics, setPhaseDiagnostics] = useState(false)
+  const [now, setNow] = useState(() => new Date())
 
-  // ─── Auto-redirect when no session_key is supplied ───
+  // Keep schedule-adjacent UI (countdown) moving; Live/completion come from context.
-  const seasonsQuery = useQuery({
+  useEffect(() => {
-    queryKey: ['seasons'],
+    const id = window.setInterval(() => setNow(new Date()), 1000)
-    queryFn: fetchSeasons,
+    return () => window.clearInterval(id)
-    enabled: sessionKey === 0,
+  }, [])
-  })
+
-
+  const contextQuery = useQuery({
-  const latestSeason = seasonsQuery.data?.[0] ?? null
+    queryKey: ['weekend-context'],
-
+    queryFn: fetchWeekendContext,
-  const meetingsQuery = useQuery({
+    staleTime: 15_000,
-    queryKey: ['meetings', latestSeason],
+    refetchInterval: 30_000,
-    queryFn: () => fetchLocalMeetings(latestSeason!),
-    enabled: sessionKey === 0 && latestSeason != null,
-  })
-
-  const focusMeeting = useMemo(() => {
-    if (sessionKey !== 0 || !meetingsQuery.data) return null
-    return pickFocusMeeting(meetingsQuery.data, new Date())
-  }, [sessionKey, meetingsQuery.data])
-
-  const fallbackWeekendQuery = useQuery({
-    queryKey: ['weekend', focusMeeting?.meeting_key],
-    queryFn: () => fetchWeekend(focusMeeting!.meeting_key),
-    enabled: sessionKey === 0 && focusMeeting != null,
   })
+  const context = contextQuery.data ?? null
 
+  // Bare `/race-hub` resolves only through canonical Weekend Context.
   useEffect(() => {
     if (sessionKey !== 0) return
-    const weekend = fallbackWeekendQuery.data
+    if (!contextQuery.isSuccess || !context) return
-    if (!weekend) return
+    const target = defaultAnalysisSessionKey(context)
-    const target = pickAnalysisSession(weekend)?.session.session_key
-      ?? weekend.default_session_key
-      ?? weekend.sessions[0]?.session.session_key
     if (target) {
       navigate({ to: '/race-hub', search: { session_key: target }, replace: true })
     }
-  }, [sessionKey, fallbackWeekendQuery.data, navigate])
+  }, [sessionKey, contextQuery.isSuccess, context, navigate])
 
-  // ─── Active session payload ───
   const raceHubQuery = useQuery({
     queryKey: ['race-hub', sessionKey],
     queryFn: () => fetchRaceHub(sessionKey),
@@ -108,37 +91,86 @@ export function RaceHubPage({ sessionKey }: Props) {
   const accent = countryAccent(data?.meeting ?? null)
   const accentStyle = { '--gp-accent': accent } as React.CSSProperties
 
-  // ─── No session_key: show resolving state, fall back to switcher if no local data ───
+  const openDiagnostics = () => {
+    setActiveTab('data_status')
+    setShowDiagnostics(true)
+    setPhaseDiagnostics(true)
+  }
+
+  // ─── No session_key: resolve via Weekend Context ───
   if (sessionKey === 0) {
-    if (seasonsQuery.isLoading || meetingsQuery.isLoading || fallbackWeekendQuery.isLoading) {
+    if (contextQuery.isLoading) {
       return (
         <div className="rh-page" style={accentStyle}>
-          <div className="loading-state">resolving latest local weekend…</div>
+          <div className="loading-state">resolving weekend context…</div>
         </div>
       )
     }
-    const seasons = seasonsQuery.data ?? []
+    if (contextQuery.isError) {
-    if (seasons.length === 0) {
       return (
-        <div className="rh-page rh-empty" data-testid="race-hub-empty" style={accentStyle}>
+        <div className="rh-page" data-testid="race-hub-error" style={accentStyle}>
-          <div className="rh-empty-band">
+          <div className="rh-recover">
-            <span className="rh-empty-eyebrow mono">box-box · race hub</span>
+            <div className="error-box">
-            <h1 className="rh-empty-title">No local sessions yet</h1>
+              {contextQuery.error instanceof Error
-            <p className="rh-empty-sub">
+                ? contextQuery.error.message
-              The Race Hub reads from local ingest only. Once a weekend is ingested
+                : 'Failed to load weekend context.'}
-              it will open here automatically.
+            </div>
-            </p>
+            <div className="rh-recover-actions">
-            <div className="rh-empty-actions">
+              <button
-              <a href="/admin" className="rh-empty-action">Open Admin · Data Health</a>
+                type="button"
-              <a href="/" className="rh-empty-action">Back to Command Center</a>
+                className="rh-recover-btn primary"
+                onClick={() => contextQuery.refetch()}
+                data-testid="rh-retry"
+              >
+                Retry
+              </button>
+              <Link to="/" search={{}} className="rh-recover-btn" data-testid="rh-back-weekend">
+                Back to Weekend
+              </Link>
             </div>
           </div>
         </div>
       )
     }
+
+    if (context && !defaultAnalysisSessionKey(context)) {
+      return (
+        <div className="rh-page rh-empty" data-testid="race-hub-no-analysis" style={accentStyle}>
+          <div className="rh-empty-band">
+            <span className="rh-empty-eyebrow mono">box-box · race hub</span>
+            <h1 className="rh-empty-title">No completed session to analyse yet</h1>
+            <p className="rh-empty-sub">
+              Weekend Context has no default analysis session. Pick a past session
+              to review, or check back once a session completes with local analysis.
+            </p>
+            <div className="rh-empty-actions">
+              <button
+                type="button"
+                className="rh-empty-action"
+                onClick={() => setSwitcherOpen(true)}
+              >
+                Browse Weekends
+              </button>
+              <Link to="/" search={{}} className="rh-empty-action" data-testid="rh-back-weekend">
+                Back to Weekend
+              </Link>
+            </div>
+          </div>
+          {switcherOpen && (
+            <WeekendSwitcher
+              currentMeetingKey={context.focus_meeting?.meeting_key}
+              context={context}
+              now={now}
+              onClose={() => setSwitcherOpen(false)}
+            />
+          )}
+        </div>
+      )
+    }
+
     return (
       <div className="rh-page" style={accentStyle}>
-        <div className="loading-state">resolving latest local weekend…</div>
+        <div className="loading-state">resolving weekend context…</div>
       </div>
     )
   }
@@ -152,12 +184,39 @@ export function RaceHubPage({ sessionKey }: Props) {
     )
   }
   if (raceHubQuery.isError || !data) {
+    const backMeeting =
+      context?.focus_meeting?.meeting_key ??
+      context?.previous_completed_session?.meeting?.meeting_key
+    const backSearch = weekendFocusSearch(backMeeting, sessionKey)
+
     return (
-      <div className="rh-page" style={accentStyle}>
+      <div className="rh-page" data-testid="race-hub-error" style={accentStyle}>
-        <div className="error-box">
+        <div className="rh-recover">
-          {raceHubQuery.error instanceof Error
+          <div className="error-box">
-            ? raceHubQuery.error.message
+            {raceHubQuery.error instanceof Error
-            : `Failed to load session ${sessionKey}.`}
+              ? raceHubQuery.error.message
+              : `Failed to load session ${sessionKey}.`}
+          </div>
+          <div className="rh-recover-actions">
+            <button
+              type="button"
+              className="rh-recover-btn primary"
+              onClick={() => raceHubQuery.refetch()}
+              data-testid="rh-retry"
+            >
+              Retry
+            </button>
+            <Link
+              to="/"
+              search={backSearch}
+              className="rh-recover-btn"
+              data-testid="rh-back-weekend"
+              data-meeting-key={backMeeting ?? undefined}
+              data-session-key={sessionKey}
+            >
+              Back to Weekend
+            </Link>
+          </div>
         </div>
       </div>
     )
@@ -168,12 +227,30 @@ export function RaceHubPage({ sessionKey }: Props) {
   const sessionMeta = weekend
     ? Object.fromEntries(weekend.sessions.map((w) => [w.session.session_key, w]))
     : {}
-  const activeSessionMeta = sessionMeta[sessionKey]
+  const activeSessionMeta: WeekendSession | undefined = sessionMeta[sessionKey]
+  const activeState = resolveSessionState({
+    weekendSession: activeSessionMeta,
+    context,
+    now,
+  })
+  const preSession = isPreSession(activeState)
+  const preparing = isPreparing(activeState)
+  const unavailable = isUnavailable(activeState)
+  const partial = isPartialAnalysis(activeState)
 
   return (
     <div className="rh-page" data-testid="race-hub" style={accentStyle}>
-      {/* Topbar */}
       <div className="rh-topbar">
+        <Link
+          to="/"
+          search={weekendFocusSearch(meetingKey, sessionKey)}
+          className="rh-back-weekend"
+          data-testid="rh-back-weekend"
+          data-meeting-key={meetingKey ?? undefined}
+          data-session-key={sessionKey}
+        >
+          Back to Weekend
+        </Link>
         <span className="rh-topbar-label mono">
           box-box · race hub
           {data.meeting?.year ? ` · ${data.meeting.year}` : ''}
@@ -195,11 +272,12 @@ export function RaceHubPage({ sessionKey }: Props) {
         <WeekendSwitcher
           currentMeetingKey={meetingKey}
           currentSessionKey={sessionKey}
+          context={context}
+          now={now}
           onClose={() => setSwitcherOpen(false)}
         />
       )}
 
-      {/* GP Identity band */}
       {data.meeting && (
         <section className="rh-identity" data-testid="rh-identity">
           <div className="rh-identity-accent" aria-hidden="true" />
@@ -220,12 +298,16 @@ export function RaceHubPage({ sessionKey }: Props) {
         </section>
       )}
 
-      {/* Session rail */}
       {sessions.length > 0 && (
         <nav className="rh-session-rail" aria-label="Weekend sessions" data-testid="rh-session-rail">
           {sessions.map((session) => {
             const meta = sessionMeta[session.session_key]
             const active = session.session_key === sessionKey
+            const state = resolveSessionState({
+              weekendSession: meta,
+              context,
+              now,
+            })
             return (
               <button
                 key={session.session_key}
@@ -247,123 +329,166 @@ export function RaceHubPage({ sessionKey }: Props) {
                 <span className="rh-session-time mono">
                   {formatSessionScheduleTime(session.date_start)}
                 </span>
-                {meta && (
+                <span className="rh-session-cov mono">
-                  <span className="rh-session-cov mono">
+                  <span
-                    <span
+                    className={`cc-cov-dot ${sessionStateDotClass(state)}`}
-                      className={`cc-cov-dot cc-cov-${meta.source}`}
+                    aria-hidden="true"
-                      aria-hidden="true"
+                  />
-                    />
+                  {sessionStateLabel(state)}
-                    {formatCoverageHint(meta.datasets)}
+                </span>
-                  </span>
-                )}
               </button>
             )
           })}
         </nav>
       )}
 
-      {/* Active session sub-bar */}
       {data.session && (
         <div className="rh-active-bar" data-testid="rh-active-bar">
           <span className="rh-active-name">{data.session.session_name}</span>
           <span className="rh-active-meta mono">
             {formatSessionScheduleTime(data.session.date_start)}
           </span>
-          {activeSessionMeta && (
+          <span className="rh-active-cov mono" data-testid="rh-active-state">
-            <span className="rh-active-cov mono">
+            <span
-              <span
+              className={`cc-cov-dot ${sessionStateDotClass(activeState)}`}
-                className={`cc-cov-dot cc-cov-${activeSessionMeta.source}`}
+              aria-hidden="true"
-                aria-hidden="true"
+            />
-              />
+            {sessionStateLabel(activeState)}
-              {formatCoverageHint(activeSessionMeta.datasets)} datasets local
+          </span>
-            </span>
-          )}
           <span className="rh-active-key mono">key {sessionKey}</span>
         </div>
       )}
 
-      <DatasetStrip datasets={data.datasets} />
+      {preSession && data.session ? (
-
+        <PreSessionView
-      <TabBar active={activeTab} onChange={setActiveTab} />
+          session={data.session}
-
+          sessionName={data.session.session_name}
-      {activeTab === 'overview' && <OverviewView data={data} />}
+          now={now}
-
+        />
-      {activeTab === 'race_story' && (
+      ) : preparing || unavailable ? (
-        <div className="data-section">
+        <>
-          <RaceStoryCanvas data={data} />
+          <SessionPhaseView
-        </div>
+            state={
-      )}
+              unavailable
-
+                ? activeState === 'cancelled'
-      {activeTab === 'strategy' && (
+                  ? 'cancelled'
-        <div className="data-section">
+                  : 'unavailable'
-          <div className="sec-header">
+                : 'preparing'
-            <span className="sec-title">Race Strategy</span>
+            }
-          </div>
+            sessionName={data.session?.session_name ?? `Session ${sessionKey}`}
-          <StrategyView
+            onOpenDiagnostics={openDiagnostics}
-            results={data.results}
-            stints={data.stints}
-            pit_stops={data.pit_stops}
-            hasStints={data.datasets['stints']?.status === 'available'}
           />
-        </div>
+          {phaseDiagnostics && (
-      )}
+            <div className="data-section" data-testid="rh-phase-diagnostics">
+              <div className="sec-header">
+                <span className="sec-title">Diagnostics</span>
+              </div>
+              <DatasetStatusView datasets={data.datasets} />
+              <div style={{ marginTop: 'var(--s5)' }} data-testid="rh-dataset-strip">
+                <DatasetStrip datasets={data.datasets} />
+              </div>
+            </div>
+          )}
+        </>
+      ) : (
+        <>
+          {partial && <PartialAnalysisBanner onOpenDiagnostics={openDiagnostics} />}
+          <TabBar active={activeTab} onChange={setActiveTab} />
 
-      {activeTab === 'compare' && (
+          {activeTab === 'overview' && <OverviewView data={data} />}
-        <div className="data-section">
-          <div className="sec-header">
-            <span className="sec-title">Driver Compare</span>
-          </div>
-          <CompareView
-            sessionKey={sessionKey}
-            results={data.results}
-            drivers={data.drivers}
-          />
-        </div>
-      )}
 
-      {activeTab === 'lap_data' && (
+          {activeTab === 'race_story' && (
-        <div className="data-section">
+            <div className="data-section">
-          <div className="sec-header">
+              <RaceStoryCanvas data={data} />
-            <span className="sec-title">Lap Data</span>
+            </div>
-            {data.laps.length > 0 && (
+          )}
-              <span className="sec-meta mono">{data.laps.length} samples</span>
-            )}
-          </div>
-          <LapsView laps={data.laps} drivers={data.drivers} />
-        </div>
-      )}
 
-      {activeTab === 'conditions' && (
+          {activeTab === 'strategy' && (
-        <div className="data-section">
+            <div className="data-section">
-          <div className="sec-header">
+              <div className="sec-header">
-            <span className="sec-title">Conditions</span>
+                <span className="sec-title">Race Strategy</span>
-            {data.weather.length > 0 && (
+              </div>
-              <span className="sec-meta mono">{data.weather.length} samples</span>
+              <StrategyView
-            )}
+                results={data.results}
-          </div>
+                stints={data.stints}
-          <WeatherView weather={data.weather} />
+                pit_stops={data.pit_stops}
-        </div>
+                hasStints={data.datasets['stints']?.status === 'available'}
-      )}
+              />
+            </div>
+          )}
 
-      {activeTab === 'race_control' && (
+          {activeTab === 'compare' && (
-        <div className="data-section">
+            <div className="data-section">
-          <div className="sec-header">
+              <div className="sec-header">
-            <span className="sec-title">Race Control</span>
+                <span className="sec-title">Driver Compare</span>
-            {data.race_control.length > 0 && (
+              </div>
-              <span className="sec-meta mono">{data.race_control.length} messages</span>
+              <CompareView
-            )}
+                sessionKey={sessionKey}
-          </div>
+                results={data.results}
-          <RaceControlView messages={data.race_control} />
+                drivers={data.drivers}
-        </div>
+              />
-      )}
+            </div>
+          )}
 
-      {activeTab === 'data_status' && (
+          {activeTab === 'lap_data' && (
-        <div className="data-section">
+            <div className="data-section">
-          <div className="sec-header">
+              <div className="sec-header">
-            <span className="sec-title">Data Status</span>
+                <span className="sec-title">Lap Data</span>
-          </div>
+                {data.laps.length > 0 && (
-          <DatasetStatusView datasets={data.datasets} />
+                  <span className="sec-meta mono">{data.laps.length} samples</span>
-        </div>
+                )}
+              </div>
+              <LapsView laps={data.laps} drivers={data.drivers} />
+            </div>
+          )}
+
+          {activeTab === 'conditions' && (
+            <div className="data-section">
+              <div className="sec-header">
+                <span className="sec-title">Conditions</span>
+                {data.weather.length > 0 && (
+                  <span className="sec-meta mono">{data.weather.length} samples</span>
+                )}
+              </div>
+              <WeatherView weather={data.weather} />
+            </div>
+          )}
+
+          {activeTab === 'race_control' && (
+            <div className="data-section">
+              <div className="sec-header">
+                <span className="sec-title">Race Control</span>
+                {data.race_control.length > 0 && (
+                  <span className="sec-meta mono">{data.race_control.length} messages</span>
+                )}
+              </div>
+              <RaceControlView messages={data.race_control} />
+            </div>
+          )}
+
+          {activeTab === 'data_status' && (
+            <div className="data-section">
+              <div className="sec-header">
+                <span className="sec-title">Diagnostics</span>
+                <button
+                  type="button"
+                  className={`rh-diagnostics-toggle${showDiagnostics ? ' active' : ''}`}
+                  onClick={() => setShowDiagnostics((v) => !v)}
+                  aria-expanded={showDiagnostics}
+                  data-testid="rh-diagnostics-toggle"
+                >
+                  {showDiagnostics ? 'Hide dataset coverage' : 'Show dataset coverage'}
+                </button>
+              </div>
+              <DatasetStatusView datasets={data.datasets} />
+              {showDiagnostics && (
+                <div style={{ marginTop: 'var(--s5)' }} data-testid="rh-dataset-strip">
+                  <DatasetStrip datasets={data.datasets} />
+                </div>
+              )}
+            </div>
+          )}
+        </>
       )}
     </div>
   )

frontend/src/pages/RacePreviewPage.tsx

@@ -0,0 +1,442 @@
+import { useEffect, useMemo, useState, type ReactNode } from 'react'
+import { useQuery } from '@tanstack/react-query'
+import {
+  fetchChampionshipHub,
+  fetchMeetings,
+  fetchResults,
+  fetchSeasons,
+  fetchSessions,
+  fetchStartingGrid,
+  fetchTrackOutline,
+} from '../api'
+import { countryAccent, countryFlag, formatGpDateRange } from '../lib/gpIdentity'
+import {
+  buildTitleFightContext,
+  countdownTargetSession,
+  extractPodium,
+  extractPole,
+  findPriorYearMeetingByCircuit,
+  findRaceSession,
+  formatPointsGap,
+  isSprintWeekend,
+  pickPreviewMeeting,
+  RACE_WIN_POINTS,
+  SPRINT_WEEKEND_MAX_POINTS,
+} from '../lib/preview'
+import { formatCountdown, formatSessionScheduleTime, sessionStartTime, sortSessionsByStart } from '../lib/schedule'
+import { buildOutlinePath } from '../lib/trackmap'
+import { teamColor } from '../utils'
+import type { Meeting, Session, TrackOutline } from '../types'
+import '../styles/preview.css'
+
+function SectionState({
+  loading,
+  error,
+  empty,
+  emptyMessage,
+  children,
+}: {
+  loading?: boolean
+  error?: Error | null
+  empty?: boolean
+  emptyMessage?: string
+  children: ReactNode
+}) {
+  if (loading) {
+    return <div className="preview-section-state">Loading…</div>
+  }
+  if (error) {
+    return (
+      <div className="preview-section-state error">
+        {error instanceof Error ? error.message : 'Failed to load'}
+      </div>
+    )
+  }
+  if (empty) {
+    return <div className="preview-section-state">{emptyMessage ?? 'No data available'}</div>
+  }
+  return <>{children}</>
+}
+
+function TrackOutlineCard({
+  outline,
+  loading,
+  error,
+  accent,
+}: {
+  outline: TrackOutline | null | undefined
+  loading: boolean
+  error: Error | null
+  accent: string
+}) {
+  const outlinePath = useMemo(() => buildOutlinePath(outline?.points ?? []), [outline])
+
+  return (
+    <section className="preview-card" data-testid="preview-track-card">
+      <h2 className="preview-card-title">Circuit</h2>
+      <SectionState
+        loading={loading}
+        error={error}
+        empty={!outline || !outlinePath}
+        emptyMessage="Track outline unavailable for this circuit"
+      >
+        <div className="preview-track-stage" style={{ ['--preview-accent' as string]: accent }}>
+          <svg className="preview-track-svg" viewBox="0 0 100 100" role="img" aria-label="Circuit outline">
+            <path className="preview-track-shadow" d={outlinePath} />
+            <path className="preview-track-outline" d={outlinePath} />
+          </svg>
+        </div>
+      </SectionState>
+    </section>
+  )
+}
+
+function LastYearCard({
+  year,
+  loading,
+  error,
+  podium,
+  pole,
+  isFirstTime,
+}: {
+  year: number | null
+  loading: boolean
+  error: Error | null
+  podium: ReturnType<typeof extractPodium>
+  pole: ReturnType<typeof extractPole>
+  isFirstTime: boolean
+}) {
+  return (
+    <section className="preview-card" data-testid="preview-last-year-card">
+      <h2 className="preview-card-title">Last year here</h2>
+      {year != null && !isFirstTime && <p className="preview-card-sub">{year} race weekend</p>}
+      <SectionState
+        loading={loading}
+        error={error}
+        empty={isFirstTime || podium.length === 0}
+        emptyMessage={
+          isFirstTime
+            ? 'First time on the calendar — no prior race at this circuit'
+            : 'No race results available for the previous visit'
+        }
+      >
+        <div className="preview-podium">
+          {podium.map((place) => (
+            <div key={place.position} className="preview-podium-row">
+              <span className="preview-podium-pos">P{place.position}</span>
+              <span className="preview-podium-code" style={{ color: teamColor(place.team_colour) }}>
+                {place.name_acronym}
+              </span>
+              <span className="preview-podium-team">{place.team_name}</span>
+            </div>
+          ))}
+        </div>
+        {pole && (
+          <p className="preview-pole">
+            Pole: <strong style={{ color: teamColor(pole.team_colour) }}>{pole.name_acronym}</strong>{' '}
+            ({pole.team_name})
+          </p>
+        )}
+      </SectionState>
+    </section>
+  )
+}
+
+function TitleFightCard({
+  loading,
+  error,
+  drivers,
+  sprintWeekend,
+  season,
+}: {
+  loading: boolean
+  error: Error | null
+  drivers: ReturnType<typeof buildTitleFightContext>
+  sprintWeekend: boolean
+  season: number | null
+}) {
+  return (
+    <section className="preview-card preview-card--wide" data-testid="preview-title-fight-card">
+      <h2 className="preview-card-title">Title fight context</h2>
+      {season != null && <p className="preview-card-sub">{season} drivers&apos; championship · top 3</p>}
+      <SectionState
+        loading={loading}
+        error={error}
+        empty={drivers.length === 0}
+        emptyMessage="Championship standings not available"
+      >
+        <table className="preview-title-table">
+          <thead>
+            <tr>
+              <th>Driver</th>
+              <th>Pts</th>
+              <th>Gap</th>
+              <th>If win (+{RACE_WIN_POINTS})</th>
+            </tr>
+          </thead>
+          <tbody>
+            {drivers.map((d) => (
+              <tr key={d.name_acronym}>
+                <td>
+                  <span style={{ color: teamColor(d.team_colour), fontWeight: 600 }}>{d.name_acronym}</span>
+                </td>
+                <td className="mono">{d.points}</td>
+                <td className="mono">{formatPointsGap(d.gapToLeader)}</td>
+                <td className="mono">
+                  {d.position === 1 ? 'LEADER' : formatPointsGap(d.gapAfterRaceWin)}
+                </td>
+              </tr>
+            ))}
+          </tbody>
+        </table>
+        {sprintWeekend && (
+          <p className="preview-sprint-note" data-testid="preview-sprint-note">
+            Sprint weekend: up to {SPRINT_WEEKEND_MAX_POINTS} pts available (race win {RACE_WIN_POINTS} + sprint win
+            8). Max gain would reduce gaps by {SPRINT_WEEKEND_MAX_POINTS} vs a standard race win.
+          </p>
+        )}
+      </SectionState>
+    </section>
+  )
+}
+
+function PreviewHeader({
+  meeting,
+  sessions,
+  countdownSession,
+  now,
+  accent,
+}: {
+  meeting: Meeting
+  sessions: Session[]
+  countdownSession: Session | null
+  now: Date
+  accent: string
+}) {
+  const countdownTarget = countdownSession ? sessionStartTime(countdownSession) : null
+
+  return (
+    <header
+      className="preview-header"
+      data-testid="preview-header"
+      style={{ ['--preview-accent' as string]: accent }}
+    >
+      <div className="preview-header-accent" />
+      <div className="preview-header-body">
+        <div className="preview-header-top">
+          <div>
+            <h1 className="preview-gp-name">
+              {countryFlag(meeting) && <span className="preview-gp-flag">{countryFlag(meeting)}</span>}
+              {meeting.meeting_name}
+            </h1>
+            <p className="preview-circuit">
+              {meeting.circuit_short_name}
+              {meeting.location ? ` · ${meeting.location}` : ''}
+              {formatGpDateRange(meeting) ? ` · ${formatGpDateRange(meeting)}` : ''}
+            </p>
+          </div>
+          {countdownTarget && (
+            <div className="preview-countdown" data-testid="preview-countdown">
+              <span className="preview-countdown-label">
+                {countdownSession?.session_name ?? 'Next session'}
+              </span>
+              <span className="preview-countdown-value">{formatCountdown(countdownTarget, now)}</span>
+            </div>
+          )}
+        </div>
+        {sessions.length > 0 && (
+          <div className="preview-schedule" data-testid="preview-schedule">
+            {sessions.map((session) => (
+              <div key={session.session_key} className="preview-schedule-item">
+                <span className="preview-schedule-name">{session.session_name}</span>
+                <span className="preview-schedule-time">{formatSessionScheduleTime(session.date_start)}</span>
+              </div>
+            ))}
+          </div>
+        )}
+      </div>
+    </header>
+  )
+}
+
+export function RacePreviewPage() {
+  const [now, setNow] = useState(() => Date.now())
+
+  useEffect(() => {
+    const timer = window.setInterval(() => setNow(Date.now()), 1000)
+    return () => window.clearInterval(timer)
+  }, [])
+
+  const nowDate = useMemo(() => new Date(now), [now])
+
+  const seasonsQuery = useQuery({
+    queryKey: ['seasons'],
+    queryFn: fetchSeasons,
+  })
+
+  const latestSeason = seasonsQuery.data?.[0] ?? null
+
+  const meetingsQuery = useQuery({
+    queryKey: ['meetings', latestSeason, 'auto'],
+    queryFn: () => fetchMeetings(latestSeason!, 'auto'),
+    enabled: latestSeason != null,
+  })
+
+  const previewMeeting = useMemo(
+    () => pickPreviewMeeting(meetingsQuery.data ?? [], nowDate),
+    [meetingsQuery.data, nowDate],
+  )
+
+  const sessionsQuery = useQuery({
+    queryKey: ['sessions', previewMeeting?.meeting_key, 'auto'],
+    queryFn: () => fetchSessions(previewMeeting!.meeting_key, 'auto'),
+    enabled: previewMeeting != null,
+  })
+
+  const sessions = useMemo(
+    () => sortSessionsByStart(sessionsQuery.data ?? []),
+    [sessionsQuery.data],
+  )
+
+  const countdownSession = useMemo(() => countdownTargetSession(sessions, nowDate), [sessions, nowDate])
+  const sprintWeekend = useMemo(() => isSprintWeekend(sessions), [sessions])
+
+  const priorYear = previewMeeting ? previewMeeting.year - 1 : null
+
+  const priorMeetingsQuery = useQuery({
+    queryKey: ['meetings', priorYear, 'auto'],
+    queryFn: () => fetchMeetings(priorYear!, 'auto'),
+    enabled: priorYear != null && previewMeeting != null,
+  })
+
+  const priorMeeting = useMemo(
+    () => findPriorYearMeetingByCircuit(priorMeetingsQuery.data ?? [], previewMeeting?.circuit_key),
+    [priorMeetingsQuery.data, previewMeeting?.circuit_key],
+  )
+
+  const priorSessionsQuery = useQuery({
+    queryKey: ['sessions', priorMeeting?.meeting_key, 'auto'],
+    queryFn: () => fetchSessions(priorMeeting!.meeting_key, 'auto'),
+    enabled: priorMeeting != null,
+  })
+
+  const priorRaceSession = useMemo(
+    () => findRaceSession(priorSessionsQuery.data ?? []),
+    [priorSessionsQuery.data],
+  )
+
+  const priorResultsQuery = useQuery({
+    queryKey: ['results', priorRaceSession?.session_key, 'auto'],
+    queryFn: () => fetchResults(priorRaceSession!.session_key, 'auto'),
+    enabled: priorRaceSession != null,
+  })
+
+  const priorGridQuery = useQuery({
+    queryKey: ['grid', priorRaceSession?.session_key, 'auto'],
+    queryFn: () => fetchStartingGrid(priorRaceSession!.session_key, 'auto'),
+    enabled: priorRaceSession != null,
+  })
+
+  const trackOutlineQuery = useQuery({
+    queryKey: ['track-outline', previewMeeting?.circuit_key, previewMeeting?.year],
+    queryFn: () => fetchTrackOutline(previewMeeting!.circuit_key!, previewMeeting!.year),
+    enabled: previewMeeting?.circuit_key != null && previewMeeting.circuit_key > 0,
+  })
+
+  const championshipQuery = useQuery({
+    queryKey: ['championship-hub', latestSeason],
+    queryFn: () => fetchChampionshipHub(latestSeason!),
+    enabled: latestSeason != null,
+  })
+
+  const podium = useMemo(() => extractPodium(priorResultsQuery.data ?? []), [priorResultsQuery.data])
+  const pole = useMemo(() => extractPole(priorGridQuery.data ?? []), [priorGridQuery.data])
+  const titleFight = useMemo(
+    () => (championshipQuery.data ? buildTitleFightContext(championshipQuery.data) : []),
+    [championshipQuery.data],
+  )
+
+  const accent = countryAccent(previewMeeting)
+  const isFirstTimeCircuit = priorMeeting == null && priorYear != null && !priorMeetingsQuery.isLoading
+
+  if (seasonsQuery.isLoading || meetingsQuery.isLoading) {
+    return <div className="page loading-state" data-testid="preview-loading">loading preview…</div>
+  }
+
+  if (seasonsQuery.isError || meetingsQuery.isError) {
+    const err = seasonsQuery.error ?? meetingsQuery.error
+    return (
+      <div className="page error-box" data-testid="preview-error">
+        {err instanceof Error ? err.message : 'Failed to load preview'}
+      </div>
+    )
+  }
+
+  if (!previewMeeting) {
+    return (
+      <div className="preview-page" data-testid="preview-season-over">
+        <div className="preview-empty">
+          <span className="preview-empty-eyebrow mono">box-box · race preview</span>
+          <h1 className="preview-empty-title">Season complete</h1>
+          <p className="preview-empty-sub">
+            No upcoming races on the {latestSeason ?? 'current'} calendar. Check back when the next season schedule is
+            published.
+          </p>
+        </div>
+        {titleFight.length > 0 && (
+          <TitleFightCard
+            loading={championshipQuery.isLoading}
+            error={championshipQuery.isError ? (championshipQuery.error as Error) : null}
+            drivers={titleFight}
+            sprintWeekend={false}
+            season={latestSeason}
+          />
+        )}
+      </div>
+    )
+  }
+
+  return (
+    <div className="preview-page" data-testid="preview-page">
+      <PreviewHeader
+        meeting={previewMeeting}
+        sessions={sessions}
+        countdownSession={countdownSession}
+        now={nowDate}
+        accent={accent}
+      />
+
+      <div className="preview-grid">
+        <TrackOutlineCard
+          outline={trackOutlineQuery.data}
+          loading={trackOutlineQuery.isLoading}
+          error={trackOutlineQuery.isError ? (trackOutlineQuery.error as Error) : null}
+          accent={accent}
+        />
+
+        <LastYearCard
+          year={priorMeeting?.year ?? priorYear}
+          loading={priorMeetingsQuery.isLoading || priorSessionsQuery.isLoading || priorResultsQuery.isLoading}
+          error={
+            priorMeetingsQuery.isError
+              ? (priorMeetingsQuery.error as Error)
+              : priorResultsQuery.isError
+                ? (priorResultsQuery.error as Error)
+                : null
+          }
+          podium={podium}
+          pole={pole}
+          isFirstTime={isFirstTimeCircuit}
+        />
+      </div>
+
+      <TitleFightCard
+        loading={championshipQuery.isLoading}
+        error={championshipQuery.isError ? (championshipQuery.error as Error) : null}
+        drivers={titleFight}
+        sprintWeekend={sprintWeekend}
+        season={latestSeason}
+      />
+    </div>
+  )
+}

frontend/src/pages/WeekendPage.tsx

@@ -0,0 +1,113 @@
+import { useWeekendContext } from '../hooks/useWeekendContext'
+import { BetweenRacesView } from '../components/weekend/BetweenRacesView'
+import { BetweenSessionsView } from '../components/weekend/BetweenSessionsView'
+import { LiveHandoffView } from '../components/weekend/LiveHandoffView'
+import { PreSessionView } from '../components/weekend/PreSessionView'
+import { WeekendError, WeekendLimited, WeekendLoading } from '../components/weekend/StatusViews'
+import { WeekendFocusBanner } from '../components/weekend/WeekendFocusBanner'
+import { resolveViewState } from '../lib/weekendContext'
+import type {
+  WeekendBriefingItem,
+  WeekendChampionshipImpact,
+  WeekendContext,
+  WeekendViewState,
+} from '../types'
+import '../styles/weekend.css'
+
+interface RenderArgs {
+  context: WeekendContext
+  now: Date
+  championship?: WeekendChampionshipImpact
+  briefing: WeekendBriefingItem[]
+  /** When true (the /preview alias), foreground the preparation surface. */
+  preview: boolean
+}
+
+function renderState(view: WeekendViewState, args: RenderArgs) {
+  const { context, now, championship, briefing, preview } = args
+  // The /preview alias always resolves to the preparation surface as long as
+  // there is a next event to prepare for, regardless of the temporal state. This
+  // keeps saved /preview links and the "Prepare for …" CTA meaningful instead of
+  // redirecting straight back to the same between-races screen.
+  if (preview && context.next_meeting) {
+    return <PreSessionView context={context} now={now} />
+  }
+
+  switch (view) {
+    case 'no_season':
+      return <WeekendLimited season={context.season} />
+    case 'between_weekends':
+    case 'post_weekend':
+    case 'season_complete':
+      return (
+        <BetweenRacesView
+          context={context}
+          now={now}
+          view={view}
+          championship={championship}
+          briefing={briefing}
+        />
+      )
+    case 'between_sessions':
+    case 'session_settling':
+      return <BetweenSessionsView context={context} now={now} view={view} briefing={briefing} />
+    case 'session_live':
+      return <LiveHandoffView context={context} />
+    case 'pre_session':
+      return <PreSessionView context={context} now={now} />
+    default:
+      return <WeekendLimited season={context.season} />
+  }
+}
+
+export function WeekendPage({
+  preview = false,
+  focusMeetingKey,
+  focusSessionKey,
+}: {
+  preview?: boolean
+  /** Restored from `/?meeting_key=` when returning from Race Hub analysis. */
+  focusMeetingKey?: number
+  /** Restored from `/?session_key=` when returning from Race Hub analysis. */
+  focusSessionKey?: number
+}) {
+  const { context, loadState, error, championship, briefing, now } = useWeekendContext()
+  const hasFocus =
+    (focusMeetingKey != null && focusMeetingKey > 0) ||
+    (focusSessionKey != null && focusSessionKey > 0)
+
+  if (loadState === 'loading') {
+    return (
+      <main className="wk-page" data-testid="weekend-page" data-state="loading">
+        <WeekendLoading />
+      </main>
+    )
+  }
+
+  if (loadState === 'error' || context == null) {
+    return (
+      <main className="wk-page" data-testid="weekend-page" data-state="error">
+        <WeekendError message={error?.message} />
+      </main>
+    )
+  }
+
+  const view = resolveViewState(context)
+
+  return (
+    <main
+      className="wk-page"
+      data-testid="weekend-page"
+      data-state={view}
+      data-temporal-state={context.temporal_state}
+      data-preview={preview ? 'true' : undefined}
+      data-meeting-key={focusMeetingKey ?? undefined}
+      data-session-key={focusSessionKey ?? undefined}
+    >
+      {hasFocus && (
+        <WeekendFocusBanner meetingKey={focusMeetingKey} sessionKey={focusSessionKey} />
+      )}
+      {renderState(view, { context, now, championship, briefing, preview })}
+    </main>
+  )
+}

frontend/src/router.tsx

@@ -1,14 +1,17 @@
 import { createRootRoute, createRoute, createRouter, Outlet } from '@tanstack/react-router'
 import { Nav } from './components/Nav'
-import { CommandCenterPage } from './pages/CommandCenterPage'
+import { WeekendPage } from './pages/WeekendPage'
+import { ExplorePage } from './pages/ExplorePage'
 import { RaceHubPage } from './pages/RaceHubPage'
 import { DataLibraryPage } from './pages/DataLibraryPage'
 import { LiveTimingPage } from './pages/LiveTimingPage'
 import { BriefingPage } from './pages/BriefingPage'
 import { ChampionshipPage } from './pages/ChampionshipPage'
+import { DriverProfilePage } from './pages/DriverProfilePage'
+import { parseRaceHubSearch, parseWeekendSearch } from './lib/routeSearch'
 
-type RaceHubSearch = {
+type DriverProfileSearch = {
-  session_key?: number
+  year?: number
 }
 
 const rootRoute = createRootRoute({
@@ -20,19 +23,31 @@ const rootRoute = createRootRoute({
   ),
 })
 
-export const commandCenterRoute = createRoute({
+// Weekend is the adaptive home. `/` renders the current temporal state.
+// Optional meeting_key/session_key search restores Race Hub return context
+// (deep-linkable, reload-safe — no hidden component memory).
+export const weekendRoute = createRoute({
   getParentRoute: () => rootRoute,
   path: '/',
-  component: CommandCenterPage,
+  validateSearch: (search: Record<string, unknown>) => parseWeekendSearch(search),
+  component: function WeekendRoute() {
+    const { meeting_key, session_key } = weekendRoute.useSearch()
+    return (
+      <WeekendPage focusMeetingKey={meeting_key} focusSessionKey={session_key} />
+    )
+  },
+})
+
+export const exploreRoute = createRoute({
+  getParentRoute: () => rootRoute,
+  path: '/explore',
+  component: ExplorePage,
 })
 
 export const raceHubRoute = createRoute({
   getParentRoute: () => rootRoute,
   path: '/race-hub',
-  validateSearch: (search: Record<string, unknown>): RaceHubSearch => {
+  validateSearch: (search: Record<string, unknown>) => parseRaceHubSearch(search),
-    const sessionKey = Number(search.session_key)
-    return Number.isFinite(sessionKey) && sessionKey > 0 ? { session_key: sessionKey } : {}
-  },
   component: function RaceHubRoute() {
     const { session_key } = raceHubRoute.useSearch()
     return <RaceHubPage sessionKey={session_key ?? 0} />
@@ -64,20 +79,49 @@ export const championshipRoute = createRoute({
   component: ChampionshipPage,
 })
 
+export const driverProfileRoute = createRoute({
+  getParentRoute: () => rootRoute,
+  path: '/drivers/$driverNumber',
+  validateSearch: (search: Record<string, unknown>): DriverProfileSearch => {
+    const year = Number(search.year)
+    return Number.isFinite(year) && year > 0 ? { year } : {}
+  },
+  component: function DriverProfileRoute() {
+    const { driverNumber } = driverProfileRoute.useParams()
+    const { year } = driverProfileRoute.useSearch()
+    return <DriverProfilePage driverNumber={Number(driverNumber) || 0} year={year} />
+  },
+})
+
 export const briefingRoute = createRoute({
   getParentRoute: () => rootRoute,
   path: '/briefing',
   component: BriefingPage,
 })
 
+// Preview folds into the Weekend home. /preview is a stable alias that renders the
+// Weekend page in its preparation surface (PreSessionView) whenever there is a next
+// event — so saved preview links and the "Prepare for …" CTA reach real preview
+// content instead of redirecting back to the same between-races screen.
+export const previewRoute = createRoute({
+  getParentRoute: () => rootRoute,
+  path: '/preview',
+  component: function PreviewRoute() {
+    return <WeekendPage preview />
+  },
+})
+
 const routeTree = rootRoute.addChildren([
-  commandCenterRoute,
+  weekendRoute,
+  exploreRoute,
   raceHubRoute,
   adminRoute,
   dataLibraryRoute,
   liveTimingRoute,
   championshipRoute,
+  driverProfileRoute,
   briefingRoute,
+  previewRoute,
 ])
 
 export const router = createRouter({ routeTree })

frontend/src/styles/app.css

@@ -142,6 +142,53 @@ a { color: inherit; text-decoration: none; }
   background: var(--surface-2);
 }
 
+/* ── Mobile bottom nav ── */
+.app-bottom-nav {
+  display: none;
+  position: fixed;
+  bottom: 0;
+  left: 0;
+  right: 0;
+  z-index: 100;
+  height: 60px;
+  padding-bottom: env(safe-area-inset-bottom, 0);
+  background: rgba(18, 18, 18, 0.92);
+  backdrop-filter: blur(16px);
+  -webkit-backdrop-filter: blur(16px);
+  border-top: 1px solid rgba(255, 255, 255, 0.08);
+}
+.bottom-nav-link {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: 3px;
+  font-size: 10px;
+  font-weight: 600;
+  color: var(--text-3);
+}
+.bottom-nav-link.active { color: var(--red); }
+.bottom-nav-link:hover { color: var(--text-2); }
+
+@media (max-width: 640px) {
+  /* On mobile the bottom bar is the single primary navigation system. The top
+     bar's Primary links are hidden so the two are never both shown; the top bar
+     keeps only the logo and the Admin operator utility. */
+  .app-bottom-nav { display: flex; }
+  .app-nav .nav-links { display: none; }
+  .app-nav { justify-content: space-between; }
+  /* Keep page content clear of the fixed bottom bar. */
+  .wk-page { padding-bottom: calc(60px + env(safe-area-inset-bottom, 0) + var(--s4)); }
+}
+
+/* ── Focus visibility (accessibility) ── */
+:focus-visible {
+  outline: 2px solid var(--red);
+  outline-offset: 2px;
+  border-radius: 3px;
+}
+
 /* ── Page ── */
 .page {
   max-width: 1040px;
@@ -1773,6 +1820,163 @@ a { color: inherit; text-decoration: none; }
 .tab-btn:hover { color: var(--text-2); }
 .tab-btn.active { color: var(--text); border-bottom-color: var(--red); }
 
+/* ── Grouped analysis navigation ── */
+.tab-bar-grouped {
+  gap: var(--s5);
+  align-items: flex-end;
+}
+.tab-group {
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  flex-shrink: 0;
+}
+.tab-group + .tab-group {
+  border-left: 1px solid var(--border);
+  padding-left: var(--s5);
+}
+.tab-group-label {
+  font-size: 9px;
+  letter-spacing: 0.12em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  opacity: 0.7;
+  padding: 0 14px;
+}
+.tab-group-btns {
+  display: flex;
+}
+
+/* ── Session lifecycle state dots ── */
+.rh-state-ready { background: var(--green); }
+.rh-state-partial { background: var(--yellow); }
+.rh-state-live { background: var(--red); }
+.rh-state-upcoming { background: var(--text-3); }
+.rh-state-preparing { background: var(--text-3); opacity: 0.5; }
+.rh-state-unavailable { background: var(--text-3); opacity: 0.4; }
+.rh-state-cancelled { background: var(--text-3); opacity: 0.35; }
+
+/* ── Pre-session (expected availability) view ── */
+.rh-presession {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s5);
+}
+.rh-presession-band {
+  padding: var(--s6) var(--s5);
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-left: 3px solid var(--gp-accent);
+  border-radius: 4px;
+  display: flex;
+  flex-direction: column;
+  gap: var(--s3);
+}
+.rh-presession-eyebrow {
+  font-size: 10px;
+  letter-spacing: 0.14em;
+  text-transform: uppercase;
+  color: var(--text-3);
+}
+.rh-presession-title {
+  font-size: 22px;
+  font-weight: 700;
+  margin: 0;
+}
+.rh-presession-sub { color: var(--text-2); max-width: 60ch; }
+.rh-presession-countdown {
+  font-size: 15px;
+  color: var(--text);
+  margin-top: var(--s3);
+}
+.rh-partial-banner {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--s3);
+  margin: 0 var(--s5) var(--s3);
+  padding: var(--s3) var(--s4);
+  border: 1px solid color-mix(in srgb, var(--yellow) 45%, var(--border));
+  background: color-mix(in srgb, var(--yellow) 12%, transparent);
+  color: var(--text-2);
+  font-size: 12px;
+}
+.rh-partial-banner-link {
+  appearance: none;
+  background: transparent;
+  border: 0;
+  color: var(--text);
+  text-decoration: underline;
+  cursor: pointer;
+  font: inherit;
+}
+.rh-expected-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
+  gap: var(--s4);
+}
+.rh-expected-card {
+  padding: var(--s4);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--surface);
+  display: flex;
+  align-items: center;
+  gap: var(--s3);
+  color: var(--text-2);
+  font-size: 13px;
+}
+.rh-expected-card .rh-expected-dot {
+  width: 6px;
+  height: 6px;
+  border-radius: 50%;
+  background: var(--text-3);
+  opacity: 0.6;
+}
+
+/* ── Loading / error recovery ── */
+.rh-recover {
+  display: flex;
+  flex-direction: column;
+  align-items: flex-start;
+  gap: var(--s4);
+  padding: var(--s6) var(--s5);
+}
+.rh-recover-actions {
+  display: flex;
+  gap: var(--s3);
+  flex-wrap: wrap;
+}
+.rh-recover-btn {
+  padding: 8px 14px;
+  font-size: 12px;
+  font-weight: 600;
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--surface);
+  color: var(--text);
+  cursor: pointer;
+  text-decoration: none;
+}
+.rh-recover-btn:hover { border-color: var(--gp-accent); }
+.rh-recover-btn.primary { border-color: var(--red); color: var(--text); }
+
+/* ── Diagnostics (secondary) action ── */
+.rh-diagnostics-toggle {
+  align-self: flex-start;
+  margin-left: auto;
+  padding: 6px 12px;
+  font-size: 11px;
+  font-weight: 600;
+  color: var(--text-3);
+  background: none;
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  cursor: pointer;
+}
+.rh-diagnostics-toggle:hover { color: var(--text-2); border-color: var(--gp-accent); }
+.rh-diagnostics-toggle.active { color: var(--text); }
+
 /* ── Dataset status view ── */
 .ds-legend {
   display: flex;
@@ -2622,6 +2826,31 @@ a { color: inherit; text-decoration: none; }
 
 .rh-topbar-spacer { flex: 1; }
 
+.rh-back-weekend {
+  flex-shrink: 0;
+  padding: 4px 10px;
+  font-size: 10px;
+  font-weight: 700;
+  font-family: var(--f-mono);
+  letter-spacing: 0.08em;
+  text-transform: uppercase;
+  color: var(--text-2);
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 2px;
+  transition: color 0.1s, border-color 0.1s, background 0.1s;
+}
+.rh-back-weekend:hover,
+.rh-back-weekend:focus-visible {
+  color: var(--text);
+  border-color: var(--gp-accent);
+  background: var(--surface-h);
+  outline: none;
+}
+.rh-back-weekend:focus-visible {
+  box-shadow: 0 0 0 2px color-mix(in srgb, var(--gp-accent) 45%, transparent);
+}
+
 .rh-switcher-toggle {
   padding: 4px 10px;
   font-size: 10px;
@@ -3197,7 +3426,10 @@ a { color: inherit; text-decoration: none; }
   .rh-overview-row { grid-template-columns: 1fr; }
 }
 @media (max-width: 640px) {
-  .rh-page { padding: var(--s4); gap: var(--s4); }
+  .rh-page { padding: var(--s4); gap: var(--s4); padding-bottom: 88px; }
+  .rh-topbar { flex-wrap: wrap; gap: var(--s3); }
+  .rh-topbar-spacer { display: none; }
+  .rh-back-weekend { order: -1; }
   .rh-identity-body { padding: var(--s3) var(--s4); gap: var(--s3); }
   .rh-identity-decal { font-size: 28px; }
   .rh-identity-name { font-size: 17px; }

frontend/src/styles/chapters.css

@@ -0,0 +1,208 @@
+.chapter-strip {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s3);
+}
+
+.chapter-strip-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--s4);
+  flex-wrap: wrap;
+}
+
+.chapter-strip-title {
+  font-size: 11px;
+  font-weight: 600;
+  letter-spacing: 0.06em;
+  text-transform: uppercase;
+  color: var(--text-3);
+}
+
+.chapter-strip-actions {
+  display: flex;
+  align-items: center;
+  gap: var(--s2);
+}
+
+.chapter-tour-btn {
+  font-family: var(--f-mono);
+  font-size: 11px;
+  padding: var(--s1) var(--s3);
+  border: 1px solid var(--border);
+  border-radius: var(--s1);
+  background: var(--surface);
+  color: var(--text-2);
+  cursor: pointer;
+  transition: background 0.15s, border-color 0.15s, color 0.15s;
+}
+
+.chapter-tour-btn:hover,
+.chapter-tour-btn.active {
+  background: var(--surface-h);
+  border-color: var(--border-2);
+  color: var(--text);
+}
+
+.chapter-strip-scroll-wrap {
+  position: relative;
+}
+
+.chapter-strip-scroll-wrap::before,
+.chapter-strip-scroll-wrap::after {
+  content: '';
+  position: absolute;
+  top: 0;
+  bottom: var(--s2);
+  width: 28px;
+  pointer-events: none;
+  z-index: 1;
+}
+
+.chapter-strip-scroll-wrap::before {
+  left: 0;
+  background: linear-gradient(to right, var(--bg), transparent);
+}
+
+.chapter-strip-scroll-wrap::after {
+  right: 0;
+  background: linear-gradient(to left, var(--bg), transparent);
+}
+
+.chapter-strip-scroll {
+  display: flex;
+  gap: var(--s3);
+  overflow-x: auto;
+  padding-bottom: var(--s2);
+  scroll-snap-type: x mandatory;
+  -webkit-overflow-scrolling: touch;
+  scrollbar-width: thin;
+  scrollbar-color: var(--border-2) transparent;
+}
+
+.chapter-strip-scroll::-webkit-scrollbar {
+  height: 4px;
+}
+
+.chapter-strip-scroll::-webkit-scrollbar-track {
+  background: transparent;
+}
+
+.chapter-strip-scroll::-webkit-scrollbar-thumb {
+  background: var(--border-2);
+  border-radius: 999px;
+}
+
+.chapter-card {
+  flex: 0 0 min(240px, 72vw);
+  min-height: 88px;
+  display: flex;
+  flex-direction: column;
+  gap: var(--s2);
+  padding: var(--s3) var(--s4);
+  border: 1px solid var(--border);
+  border-radius: var(--s2);
+  background: var(--surface);
+  text-align: left;
+  cursor: pointer;
+  scroll-snap-align: center;
+  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
+}
+
+.chapter-card:hover {
+  background: var(--surface-h);
+  border-color: var(--border-2);
+}
+
+.chapter-card.active {
+  border-color: var(--accent, var(--red));
+  background: var(--surface-h);
+  box-shadow: 0 0 0 1px color-mix(in srgb, var(--accent, var(--red)) 35%, transparent);
+}
+
+.chapter-card.tour-active {
+  border-color: var(--yellow);
+  box-shadow: 0 0 0 1px color-mix(in srgb, var(--yellow) 40%, transparent);
+}
+
+.chapter-card-top {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--s3);
+}
+
+.chapter-kind {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-width: 28px;
+  height: 20px;
+  padding: 0 var(--s2);
+  border-radius: var(--s1);
+  font-family: var(--f-mono);
+  font-size: 10px;
+  font-weight: 700;
+  letter-spacing: 0.04em;
+  background: var(--bg);
+  color: var(--text-2);
+  border: 1px solid var(--border);
+}
+
+.chapter-card.active .chapter-kind {
+  color: var(--text);
+  border-color: var(--border-2);
+}
+
+.chapter-kind--safety_car,
+.chapter-kind--virtual_safety_car {
+  color: var(--orange, #f90);
+}
+
+.chapter-kind--red_flag {
+  color: var(--red);
+}
+
+.chapter-kind--decisive_swing {
+  color: var(--green, #22c55e);
+}
+
+.chapter-kind--finish {
+  color: var(--yellow);
+}
+
+.chapter-lap-range {
+  font-family: var(--f-mono);
+  font-size: 10px;
+  color: var(--text-3);
+  white-space: nowrap;
+}
+
+.chapter-headline {
+  font-size: 13px;
+  line-height: 1.35;
+  color: var(--text);
+  display: -webkit-box;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+  overflow: hidden;
+  flex: 1;
+}
+
+.chapter-strip-empty-card {
+  padding: var(--s6) var(--s5);
+  margin: 0;
+}
+
+.chapter-strip-empty-card .empty-state-icon {
+  display: block;
+  margin: 0 auto var(--s3);
+  color: var(--text-3);
+}
+
+@media (max-width: 900px) {
+  .chapter-strip-header {
+    align-items: flex-start;
+  }
+}

frontend/src/styles/digest.css

@@ -0,0 +1,178 @@
+/* ── Calendar-aware paddock digest ── */
+
+.digest-sticky {
+  position: sticky;
+  top: 0;
+  z-index: 20;
+  margin-bottom: var(--s5);
+  padding: var(--s4) var(--s5);
+  background: color-mix(in srgb, var(--bg) 92%, transparent);
+  backdrop-filter: blur(8px);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+}
+
+.digest-sticky-head {
+  display: flex;
+  align-items: baseline;
+  gap: var(--s3);
+  flex-wrap: wrap;
+  margin-bottom: var(--s3);
+}
+
+.digest-sticky-title {
+  font-size: 15px;
+  font-weight: 600;
+  color: var(--text);
+  margin: 0;
+}
+
+.digest-sticky-count {
+  font-size: 11px;
+  color: var(--text-3);
+  font-family: var(--f-mono);
+  letter-spacing: 0.04em;
+}
+
+.digest-sticky-tags {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--s2);
+  align-items: center;
+}
+
+.digest-tag-chip {
+  display: inline-flex;
+  align-items: center;
+  gap: var(--s2);
+  padding: 2px 8px;
+  border-radius: 999px;
+  border: 1px solid var(--border-2);
+  background: var(--surface);
+  color: var(--text-2);
+  font-size: 11px;
+  font-family: var(--f-mono);
+  cursor: pointer;
+  transition: border-color 0.1s, color 0.1s, background 0.1s;
+}
+
+.digest-tag-chip:hover {
+  color: var(--text);
+  background: var(--surface-h);
+}
+
+.digest-tag-chip.active {
+  color: var(--text);
+  border-color: var(--tag-colour, var(--red));
+  box-shadow: 0 0 0 1px color-mix(in srgb, var(--tag-colour, var(--red)) 35%, transparent);
+}
+
+.digest-tag-dot {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: var(--tag-colour, var(--text-3));
+  flex-shrink: 0;
+}
+
+.digest-filter-clear {
+  padding: 2px 8px;
+  border: 1px dashed var(--border-2);
+  border-radius: 999px;
+  background: none;
+  color: var(--text-3);
+  font-size: 11px;
+  font-family: var(--f-mono);
+  cursor: pointer;
+}
+
+.digest-filter-clear:hover {
+  color: var(--text);
+  border-color: var(--border-2);
+}
+
+.digest-section {
+  margin-bottom: var(--s6);
+}
+
+.digest-section-head {
+  display: flex;
+  align-items: baseline;
+  gap: var(--s3);
+  margin-bottom: var(--s4);
+  padding-bottom: var(--s3);
+  border-bottom: 1px solid var(--border);
+}
+
+.digest-section-title {
+  font-size: 13px;
+  font-weight: 600;
+  color: var(--text);
+  margin: 0;
+  letter-spacing: 0.02em;
+}
+
+.digest-section-count {
+  font-size: 11px;
+  color: var(--text-3);
+  font-family: var(--f-mono);
+}
+
+.digest-recent-section .digest-section-title {
+  color: var(--text-2);
+}
+
+.bp-card-tags {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--s2);
+  margin-top: var(--s2);
+}
+
+.bp-card-tag {
+  display: inline-flex;
+  align-items: center;
+  gap: 4px;
+  padding: 1px 6px;
+  border-radius: 999px;
+  border: 1px solid var(--border);
+  background: var(--bg);
+  color: var(--text-2);
+  font-size: 10px;
+  font-family: var(--f-mono);
+  cursor: pointer;
+}
+
+.bp-card-tag:hover {
+  color: var(--text);
+  border-color: var(--border-2);
+}
+
+.bp-card-tag.active {
+  border-color: var(--tag-colour, var(--red));
+}
+
+.cc-brief-digest-meta {
+  display: flex;
+  align-items: center;
+  gap: var(--s2);
+  margin-bottom: var(--s3);
+  font-size: 11px;
+  color: var(--text-3);
+  font-family: var(--f-mono);
+}
+
+.cc-brief-digest-tags {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--s2);
+}
+
+.cc-brief-tag {
+  font-size: 10px;
+  padding: 1px 6px;
+  border-radius: 999px;
+  border: 1px solid var(--border);
+  color: var(--text-2);
+  font-family: var(--f-mono);
+}

frontend/src/styles/driver-profile.css

@@ -0,0 +1,289 @@
+/* Driver profile page (/drivers/$driverNumber) */
+
+.dp-page {
+  max-width: 1100px;
+  margin: 0 auto;
+  padding: var(--s6) var(--s5);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s6);
+}
+
+/* --- header --- */
+
+.dp-header {
+  position: relative;
+  display: flex;
+  flex-wrap: wrap;
+  align-items: flex-end;
+  justify-content: space-between;
+  gap: var(--s5);
+  padding: var(--s5);
+  padding-left: var(--s6);
+  border: 1px solid var(--border);
+  border-left: 4px solid var(--red);
+  border-radius: var(--r2);
+  background: var(--surface);
+}
+
+.dp-title-row {
+  display: flex;
+  align-items: baseline;
+  gap: var(--s3);
+}
+
+.dp-code {
+  font-size: 13px;
+  letter-spacing: 0.12em;
+  color: var(--text-2);
+  text-transform: uppercase;
+}
+
+.dp-num {
+  font-size: 13px;
+  font-weight: 700;
+}
+
+.dp-name {
+  margin: var(--s2) 0;
+  font-size: 30px;
+  line-height: 1.1;
+  letter-spacing: -0.01em;
+}
+
+.dp-team {
+  display: flex;
+  align-items: center;
+  gap: var(--s3);
+  font-size: 13px;
+  color: var(--text-2);
+}
+
+.dp-team-swatch {
+  width: 10px;
+  height: 10px;
+  border-radius: 2px;
+}
+
+.dp-season {
+  color: var(--text-3);
+}
+
+.dp-stat-rail {
+  display: flex;
+  gap: var(--s5);
+}
+
+.dp-stat {
+  min-width: 72px;
+}
+
+.dp-stat-value {
+  font-size: 22px;
+  font-weight: 700;
+}
+
+.dp-stat-label {
+  font-size: 11px;
+  text-transform: uppercase;
+  letter-spacing: 0.06em;
+  color: var(--text-3);
+}
+
+.dp-back {
+  position: absolute;
+  top: var(--s4);
+  right: var(--s5);
+  font-size: 12px;
+  color: var(--text-3);
+  text-decoration: none;
+}
+
+.dp-back:hover {
+  color: var(--text);
+}
+
+/* --- sections --- */
+
+.dp-section {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s4);
+}
+
+.dp-section-title {
+  font-size: 12px;
+  text-transform: uppercase;
+  letter-spacing: 0.1em;
+  color: var(--text-2);
+}
+
+.dp-empty {
+  padding: var(--s5);
+  border: 1px dashed var(--border);
+  border-radius: var(--r2);
+  color: var(--text-3);
+  font-size: 13px;
+}
+
+/* --- charts --- */
+
+.dp-form-grid {
+  display: grid;
+  grid-template-columns: minmax(0, 2fr) minmax(200px, 1fr);
+  gap: var(--s5);
+  align-items: stretch;
+}
+
+@media (max-width: 760px) {
+  .dp-form-grid {
+    grid-template-columns: 1fr;
+  }
+}
+
+.dp-chart {
+  margin: 0;
+  padding: var(--s4);
+  border: 1px solid var(--border);
+  border-radius: var(--r2);
+  background: var(--surface);
+  min-width: 0;
+}
+
+.dp-chart-caption {
+  font-size: 11px;
+  text-transform: uppercase;
+  letter-spacing: 0.06em;
+  color: var(--text-3);
+  margin-bottom: var(--s3);
+}
+
+.dp-chart-svg {
+  display: block;
+  width: 100%;
+  height: auto;
+}
+
+.dp-chart-scroll {
+  overflow-x: auto;
+}
+
+.dp-gridline {
+  stroke: var(--border);
+  stroke-width: 1;
+}
+
+.dp-zeroline {
+  stroke: var(--text-3);
+  stroke-width: 1;
+  stroke-dasharray: 3 3;
+}
+
+.dp-axis {
+  fill: var(--text-3);
+  font-family: var(--f-mono);
+  font-size: 10px;
+}
+
+.dp-delta-svg {
+  display: block;
+}
+
+.dp-delta-val {
+  fill: var(--text-2);
+  font-size: 10px;
+}
+
+/* --- form strip --- */
+
+.dp-form-strip {
+  padding: var(--s4);
+  border: 1px solid var(--border);
+  border-radius: var(--r2);
+  background: var(--surface);
+  display: flex;
+  flex-direction: column;
+}
+
+.dp-form-bars {
+  flex: 1;
+  display: flex;
+  align-items: flex-end;
+  gap: var(--s3);
+  min-height: 110px;
+}
+
+.dp-form-bar {
+  flex: 1;
+  height: 100%;
+  display: flex;
+  flex-direction: column;
+  justify-content: flex-end;
+  align-items: center;
+  gap: var(--s2);
+}
+
+.dp-form-bar-fill {
+  width: 100%;
+  max-width: 34px;
+  border-radius: 2px 2px 0 0;
+  opacity: 0.9;
+}
+
+.dp-form-bar-val {
+  font-size: 11px;
+  color: var(--text-2);
+}
+
+/* --- rounds table --- */
+
+.dp-scroll {
+  overflow-x: auto;
+  border: 1px solid var(--border);
+  border-radius: var(--r2);
+  background: var(--surface);
+}
+
+.dp-table {
+  width: 100%;
+  border-collapse: collapse;
+  font-size: 13px;
+}
+
+.dp-table th {
+  padding: var(--s3) var(--s4);
+  font-family: var(--f-mono);
+  font-size: 11px;
+  text-transform: uppercase;
+  letter-spacing: 0.06em;
+  color: var(--text-3);
+  border-bottom: 1px solid var(--border);
+}
+
+.dp-table td {
+  padding: var(--s3) var(--s4);
+  border-bottom: 1px solid var(--border);
+  white-space: nowrap;
+}
+
+.dp-table tbody tr:last-child td {
+  border-bottom: none;
+}
+
+.dp-table th.l,
+.dp-table td.l {
+  text-align: left;
+}
+
+.dp-table th.r,
+.dp-table td.r {
+  text-align: right;
+}
+
+.dp-td-dim {
+  color: var(--text-3);
+}
+
+.dp-flag {
+  margin-right: var(--s3);
+}

frontend/src/styles/h2h.css

@@ -0,0 +1,130 @@
+/* Teammate head-to-head bars (issue #23). */
+
+.h2h-section {
+  margin: 20px 0 24px;
+  padding: 16px 18px;
+  background: var(--surface-1, rgba(255, 255, 255, 0.03));
+  border: 1px solid var(--border);
+  border-radius: 8px;
+}
+
+.h2h-section-head {
+  display: flex;
+  align-items: baseline;
+  gap: 10px;
+  margin-bottom: 14px;
+}
+
+.h2h-section-title {
+  font-size: 13px;
+  font-weight: 600;
+  letter-spacing: 0.04em;
+  text-transform: uppercase;
+  color: var(--text-2);
+}
+
+.h2h-section-sub {
+  font-size: 11px;
+  font-family: var(--f-mono);
+  color: var(--text-3);
+}
+
+.h2h-list {
+  display: flex;
+  flex-direction: column;
+  gap: 10px;
+}
+
+.h2h-row {
+  display: grid;
+  grid-template-columns: minmax(100px, 140px) 1fr;
+  align-items: center;
+  gap: 12px;
+}
+
+.h2h-team {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  min-width: 0;
+}
+
+.h2h-team-name {
+  font-size: 12px;
+  color: var(--text-2);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.h2h-extra {
+  font-size: 10px;
+  color: var(--text-3);
+  flex-shrink: 0;
+}
+
+.h2h-bar-wrap {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  min-width: 0;
+}
+
+.h2h-tla {
+  font-size: 11px;
+  font-weight: 700;
+  color: var(--text);
+  flex-shrink: 0;
+  width: 28px;
+}
+
+.h2h-tla--left {
+  text-align: right;
+}
+
+.h2h-tla--right {
+  text-align: left;
+}
+
+.h2h-bar {
+  position: relative;
+  flex: 1;
+  display: flex;
+  height: 22px;
+  border-radius: 4px;
+  overflow: hidden;
+  background: rgba(255, 255, 255, 0.04);
+}
+
+.h2h-bar-seg {
+  height: 100%;
+  transition: width 0.2s ease;
+}
+
+.h2h-bar-seg--muted {
+  opacity: 0.35;
+}
+
+.h2h-score {
+  position: absolute;
+  inset: 0;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 11px;
+  font-weight: 700;
+  color: #fff;
+  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.6);
+  pointer-events: none;
+}
+
+@media (max-width: 640px) {
+  .h2h-row {
+    grid-template-columns: 1fr;
+    gap: 4px;
+  }
+
+  .h2h-bar-wrap {
+    width: 100%;
+  }
+}

frontend/src/styles/preview.css

@@ -0,0 +1,309 @@
+.preview-page {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s6);
+  padding: var(--s6);
+  max-width: 1200px;
+  margin: 0 auto;
+}
+
+.preview-empty {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: var(--s4);
+  min-height: 320px;
+  text-align: center;
+  padding: var(--s8);
+  background: var(--surface);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  border-radius: 8px;
+}
+
+.preview-empty-eyebrow {
+  font-size: 0.7rem;
+  letter-spacing: 0.12em;
+  text-transform: uppercase;
+  color: var(--text-3);
+}
+
+.preview-empty-title {
+  font-size: 1.5rem;
+  font-weight: 600;
+  margin: 0;
+}
+
+.preview-empty-sub {
+  color: var(--text-2);
+  max-width: 36rem;
+  margin: 0;
+}
+
+.preview-header {
+  display: flex;
+  background: var(--surface);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  border-radius: 8px;
+  overflow: hidden;
+  min-height: 140px;
+}
+
+.preview-header-accent {
+  width: 4px;
+  flex-shrink: 0;
+  background: var(--preview-accent, var(--gp-accent));
+  box-shadow: 0 0 12px var(--preview-accent, var(--gp-accent));
+}
+
+.preview-header-body {
+  flex: 1;
+  padding: var(--s5);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s4);
+  min-width: 0;
+}
+
+.preview-header-top {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: flex-start;
+  justify-content: space-between;
+  gap: var(--s4);
+}
+
+.preview-gp-name {
+  font-size: 1.4rem;
+  font-weight: 600;
+  margin: 0;
+  display: flex;
+  align-items: center;
+  gap: var(--s3);
+}
+
+.preview-gp-flag {
+  font-size: 1.5rem;
+  line-height: 1;
+}
+
+.preview-circuit {
+  color: var(--text-2);
+  font-size: 0.9rem;
+  margin: 0;
+}
+
+.preview-countdown {
+  text-align: right;
+}
+
+.preview-countdown-label {
+  display: block;
+  font-size: 0.7rem;
+  letter-spacing: 0.08em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  margin-bottom: var(--s1);
+}
+
+.preview-countdown-value {
+  font-family: var(--mono);
+  font-size: 1.1rem;
+  font-variant-numeric: tabular-nums;
+  color: var(--text-1);
+}
+
+.preview-schedule {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
+  gap: var(--s2);
+}
+
+.preview-schedule-item {
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  padding: var(--s2) var(--s3);
+  background: rgba(255, 255, 255, 0.03);
+  border-radius: 4px;
+  font-size: 0.8rem;
+}
+
+.preview-schedule-name {
+  font-weight: 600;
+  color: var(--text-1);
+}
+
+.preview-schedule-time {
+  font-family: var(--mono);
+  font-size: 0.75rem;
+  color: var(--text-2);
+}
+
+.preview-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
+  gap: var(--s5);
+}
+
+.preview-card {
+  background: var(--surface);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  border-radius: 8px;
+  padding: var(--s5);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s4);
+  min-height: 200px;
+}
+
+.preview-card-title {
+  font-size: 0.75rem;
+  letter-spacing: 0.1em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  margin: 0;
+}
+
+.preview-card-sub {
+  font-size: 0.85rem;
+  color: var(--text-2);
+  margin: calc(-1 * var(--s2)) 0 0;
+}
+
+.preview-track-stage {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  flex: 1;
+  min-height: 180px;
+  padding: var(--s4);
+}
+
+.preview-track-svg {
+  width: 100%;
+  max-width: 280px;
+  height: auto;
+}
+
+.preview-track-outline {
+  fill: none;
+  stroke: var(--preview-accent, var(--gp-accent));
+  stroke-width: 1.8;
+  stroke-linecap: round;
+  stroke-linejoin: round;
+  opacity: 0.9;
+}
+
+.preview-track-shadow {
+  fill: none;
+  stroke: rgba(0, 0, 0, 0.5);
+  stroke-width: 3;
+  stroke-linecap: round;
+  stroke-linejoin: round;
+}
+
+.preview-podium {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s3);
+}
+
+.preview-podium-row {
+  display: flex;
+  align-items: center;
+  gap: var(--s3);
+  font-size: 0.9rem;
+}
+
+.preview-podium-pos {
+  width: 1.5rem;
+  font-family: var(--mono);
+  font-weight: 600;
+  color: var(--text-3);
+}
+
+.preview-podium-code {
+  font-weight: 600;
+  min-width: 2.5rem;
+}
+
+.preview-podium-team {
+  color: var(--text-2);
+  font-size: 0.8rem;
+}
+
+.preview-pole {
+  padding-top: var(--s3);
+  border-top: 1px solid rgba(255, 255, 255, 0.06);
+  font-size: 0.85rem;
+  color: var(--text-2);
+}
+
+.preview-pole strong {
+  color: var(--text-1);
+}
+
+.preview-title-table {
+  width: 100%;
+  border-collapse: collapse;
+  font-size: 0.85rem;
+}
+
+.preview-title-table th,
+.preview-title-table td {
+  padding: var(--s2) var(--s3);
+  text-align: left;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.preview-title-table th {
+  font-size: 0.7rem;
+  letter-spacing: 0.06em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  font-weight: 500;
+}
+
+.preview-title-table td.mono {
+  font-family: var(--mono);
+  font-variant-numeric: tabular-nums;
+}
+
+.preview-sprint-note {
+  font-size: 0.8rem;
+  color: var(--text-2);
+  margin: 0;
+  padding: var(--s3);
+  background: rgba(255, 255, 255, 0.03);
+  border-radius: 4px;
+}
+
+.preview-section-state {
+  flex: 1;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: var(--text-3);
+  font-size: 0.85rem;
+  text-align: center;
+  padding: var(--s5);
+}
+
+.preview-section-state.error {
+  color: var(--red, #e74c3c);
+}
+
+@media (max-width: 640px) {
+  .preview-page {
+    padding: var(--s4);
+  }
+
+  .preview-header-top {
+    flex-direction: column;
+  }
+
+  .preview-countdown {
+    text-align: left;
+  }
+}

frontend/src/styles/race-story.css

@@ -0,0 +1,157 @@
+.race-story-empty-card {
+  padding: var(--s6) var(--s5);
+  margin: 0;
+}
+
+.race-story-empty-card .empty-state-icon {
+  display: block;
+  margin: 0 auto var(--s3);
+  color: var(--text-3);
+}
+
+.rs-replay-shell {
+  display: grid;
+  grid-template-columns: 1fr;
+  gap: var(--s5);
+  align-items: stretch;
+}
+
+.rs-replay-shell--split {
+  grid-template-columns: minmax(0, 1.4fr) minmax(260px, 0.8fr);
+}
+
+.rs-replay-main {
+  min-width: 0;
+}
+
+.rs-chart-container {
+  --rs-chart-max-width: 100%;
+}
+
+.rs-chart-container--full {
+  --rs-chart-max-width: 100%;
+}
+
+.rs-segmented-control {
+  display: inline-flex;
+  align-items: stretch;
+  flex-wrap: wrap;
+  gap: 0;
+  margin-top: var(--s3);
+  border: 1px solid var(--border-2);
+  border-radius: var(--s1);
+  background: var(--surface);
+  overflow: hidden;
+}
+
+.rs-segment {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 30px;
+  padding: 0 var(--s4);
+  font-family: var(--f-mono);
+  font-size: 10px;
+  font-weight: 700;
+  letter-spacing: 0.04em;
+  color: var(--text-3);
+  background: transparent;
+  border: none;
+  border-right: 1px solid var(--border);
+  cursor: pointer;
+  transition: background 0.12s, color 0.12s;
+}
+
+.rs-segment:last-child {
+  border-right: none;
+}
+
+.rs-segment:hover:not(:disabled) {
+  color: var(--text);
+  background: var(--surface-h);
+}
+
+.rs-segment:focus-visible {
+  outline: 2px solid var(--red);
+  outline-offset: -2px;
+  z-index: 1;
+}
+
+.rs-segment.active {
+  color: var(--text);
+  background: rgba(230, 36, 41, 0.12);
+  box-shadow: inset 0 -2px 0 var(--red);
+}
+
+.rs-segment:disabled {
+  opacity: 0.45;
+  cursor: not-allowed;
+}
+
+.rs-segment-divider {
+  width: 1px;
+  align-self: stretch;
+  background: var(--border);
+  flex-shrink: 0;
+}
+
+.rs-replay-map-slot {
+  min-width: 0;
+}
+
+.rs-position-chart-svg {
+  width: 100%;
+  min-width: 280px;
+  max-width: var(--rs-chart-max-width, 640px);
+  display: block;
+}
+
+.rs-chart-axis-label {
+  fill: var(--text-3);
+  font-family: var(--f-mono);
+  font-size: 9px;
+}
+
+.rs-chart-grid-line {
+  stroke: var(--border);
+  stroke-width: 0.5;
+}
+
+.rs-chart-lap-tick {
+  stroke: var(--border);
+  stroke-width: 1;
+}
+
+@media (max-width: 900px) {
+  .rs-replay-shell--split {
+    grid-template-columns: 1fr;
+  }
+
+  .rs-segmented-control {
+    width: 100%;
+  }
+
+  .rs-segment {
+    flex: 1 1 auto;
+  }
+}
+
+@media (max-width: 560px) {
+  .rs-segmented-control {
+    flex-direction: column;
+    align-items: stretch;
+  }
+
+  .rs-segment {
+    border-right: none;
+    border-bottom: 1px solid var(--border);
+  }
+
+  .rs-segment:last-child {
+    border-bottom: none;
+  }
+
+  .rs-segment-divider {
+    display: none;
+  }
+}

frontend/src/styles/replay-map.css

@@ -0,0 +1,91 @@
+.replay-map-panel {
+  min-height: 244px;
+  height: 100%;
+  border: 1px solid var(--border);
+  background: var(--surface);
+  border-radius: var(--s2);
+}
+
+.replay-map-stage {
+  position: relative;
+  min-height: 244px;
+  height: 100%;
+}
+
+.replay-map-svg {
+  width: 100%;
+  height: 100%;
+  min-height: 244px;
+  display: block;
+  background: radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.04), transparent 62%);
+}
+
+.replay-map-outline-shadow,
+.replay-map-outline {
+  fill: none;
+  vector-effect: non-scaling-stroke;
+  stroke-linecap: round;
+  stroke-linejoin: round;
+}
+
+.replay-map-outline-shadow {
+  stroke: rgba(255, 255, 255, 0.08);
+  stroke-width: 5;
+}
+
+.replay-map-outline {
+  stroke: var(--text-2);
+  stroke-width: 1.8;
+}
+
+.replay-car {
+  cursor: pointer;
+  outline: none;
+}
+
+.replay-car circle {
+  stroke: var(--bg);
+  stroke-width: 0.8;
+  filter: drop-shadow(0 1px 3px rgba(0, 0, 0, 0.55));
+}
+
+.replay-car text {
+  fill: #fff;
+  font-family: var(--f-mono);
+  font-size: 2.6px;
+  font-weight: 800;
+  text-anchor: middle;
+  pointer-events: none;
+  paint-order: stroke;
+  stroke: rgba(0, 0, 0, 0.75);
+  stroke-width: 0.7;
+}
+
+.replay-car:not(.replay-car-pinned) text {
+  opacity: 0;
+}
+
+.replay-car:hover text,
+.replay-car:focus-visible text,
+.replay-car-pinned text {
+  opacity: 1;
+}
+
+.replay-car-pinned circle {
+  stroke: #fff;
+  stroke-width: 1.2;
+}
+
+.replay-map-empty-card {
+  min-height: 244px;
+  display: grid;
+  place-content: center;
+  padding: var(--s6);
+  margin: 0;
+}
+
+.replay-map-empty-card .empty-state-icon {
+  display: block;
+  margin: 0 auto var(--s3);
+  color: var(--text-3);
+}

frontend/src/styles/rivalry.css

@@ -0,0 +1,134 @@
+.rivalry {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s5);
+}
+
+.rivalry-pickers {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--s4);
+  align-items: flex-end;
+}
+
+.rivalry-vs {
+  font-size: 11px;
+  letter-spacing: 0.06em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  padding-bottom: var(--s3);
+}
+
+.rivalry-picker {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s2);
+  min-width: 200px;
+}
+
+.rivalry-picker-label {
+  font-family: var(--f-mono);
+  font-size: 11px;
+  letter-spacing: 0.06em;
+  text-transform: uppercase;
+  color: var(--text-3);
+}
+
+.rivalry-picker-select {
+  font-family: var(--f-mono);
+  font-size: 13px;
+  padding: var(--s2) var(--s3);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--surface-2);
+  color: var(--text);
+}
+
+.rivalry-picker-select:focus {
+  outline: 2px solid var(--red);
+  outline-offset: 1px;
+}
+
+.rivalry-h2h {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: var(--s4) var(--s5);
+  padding: var(--s4) var(--s5);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--surface-2);
+}
+
+.rivalry-h2h-score {
+  display: flex;
+  align-items: baseline;
+  gap: var(--s3);
+}
+
+.rivalry-h2h-code {
+  font-size: 14px;
+  font-weight: 700;
+}
+
+.rivalry-h2h-num {
+  font-size: 24px;
+  font-weight: 700;
+  color: var(--text);
+}
+
+.rivalry-h2h-meta {
+  font-family: var(--f-mono);
+  font-size: 11px;
+  color: var(--text-3);
+}
+
+.rivalry-strip {
+  display: flex;
+  align-items: center;
+  gap: var(--s2);
+  margin-left: auto;
+}
+
+.rivalry-strip-label {
+  font-family: var(--f-mono);
+  font-size: 10px;
+  letter-spacing: 0.06em;
+  text-transform: uppercase;
+  color: var(--text-3);
+  margin-right: var(--s2);
+}
+
+.rivalry-chip {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 1px;
+  padding: var(--s1) var(--s3);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  background: var(--surface);
+}
+
+.rivalry-chip-round {
+  font-size: 9px;
+  color: var(--text-3);
+}
+
+.rivalry-chip-winner {
+  font-size: 11px;
+  font-weight: 700;
+}
+
+.rivalry-section {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s3);
+}
+
+.rivalry-caption {
+  font-family: var(--f-mono);
+  font-size: 11px;
+  color: var(--text-3);
+  margin: 0;
+}

frontend/src/styles/weekend.css

@@ -0,0 +1,413 @@
+/* ── Weekend adaptive home ── */
+.wk-page {
+  max-width: 1280px;
+  margin: 0 auto;
+  padding: var(--s6) var(--s6) 64px;
+  width: 100%;
+}
+
+.wk-focus {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--s5);
+  margin-bottom: var(--s5);
+  padding: var(--s5);
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-left: 3px solid var(--red);
+  border-radius: 8px;
+}
+.wk-focus-copy { display: flex; flex-direction: column; gap: var(--s2); min-width: 0; }
+.wk-focus-eyebrow {
+  font-size: 10px;
+  letter-spacing: 0.12em;
+  text-transform: uppercase;
+  color: var(--text-3);
+}
+.wk-focus-title {
+  font-size: 18px;
+  font-weight: 700;
+  line-height: 1.2;
+}
+.wk-focus-session {
+  font-size: 13px;
+  color: var(--text-2);
+}
+.wk-focus-cta { flex-shrink: 0; }
+
+.wk-eyebrow {
+  display: flex;
+  align-items: center;
+  gap: var(--s4);
+  font-size: 11px;
+  font-weight: 700;
+  letter-spacing: 0.18em;
+  text-transform: uppercase;
+  color: var(--text-2);
+  margin-bottom: var(--s5);
+}
+.wk-eyebrow::after {
+  content: '';
+  flex: 1;
+  height: 1px;
+  background: linear-gradient(90deg, var(--red), transparent);
+}
+
+.wk-card-head {
+  display: flex;
+  align-items: baseline;
+  justify-content: space-between;
+  gap: var(--s4);
+  margin-bottom: var(--s4);
+}
+.wk-card-title {
+  font-size: 13px;
+  font-weight: 700;
+  color: var(--text);
+}
+.wk-card-link {
+  font-size: 11px;
+  color: var(--text-2);
+  white-space: nowrap;
+}
+.wk-card-link:hover { color: var(--text); }
+
+.wk-flag { font-size: 22px; line-height: 1; }
+
+/* ── CTAs ── */
+.wk-cta {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  gap: var(--s3);
+  padding: var(--s4) var(--s5);
+  font-size: 13px;
+  font-weight: 600;
+  border-radius: 6px;
+  transition: background 0.12s, border-color 0.12s, transform 0.12s;
+}
+.wk-cta-primary { background: var(--red); color: #fff; }
+.wk-cta-primary:hover { background: #ff3b3f; }
+.wk-cta-ghost {
+  background: transparent;
+  color: var(--text-2);
+  border: 1px solid var(--border-2);
+}
+.wk-cta-ghost:hover { color: var(--text); border-color: var(--text-3); }
+.wk-cta-wide { width: 100%; }
+
+/* ── Between-races top grid ── */
+.wk-top-grid {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: var(--s5);
+  margin-bottom: var(--s5);
+}
+.wk-mid-grid {
+  display: grid;
+  grid-template-columns: minmax(0, 340px) minmax(0, 1fr);
+  gap: var(--s5);
+  margin-bottom: var(--s5);
+}
+
+.wk-event-card {
+  min-width: 0;
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  padding: var(--s5);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s5);
+}
+.wk-event-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: var(--s4);
+}
+.wk-event-id { display: flex; align-items: center; gap: var(--s4); min-width: 0; }
+.wk-event-name {
+  font-size: 24px;
+  font-weight: 700;
+  letter-spacing: -0.01em;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+.wk-event-tag {
+  display: inline-flex;
+  align-items: center;
+  gap: 5px;
+  font-size: 10px;
+  font-weight: 700;
+  letter-spacing: 0.1em;
+  text-transform: uppercase;
+  white-space: nowrap;
+}
+.wk-tag-done { color: var(--text-2); }
+.wk-tag-next { color: var(--red); }
+
+.wk-event-body {
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) minmax(0, 200px);
+  gap: var(--s5);
+  align-items: stretch;
+}
+
+/* ── Podium ── */
+.wk-podium { list-style: none; display: flex; flex-direction: column; gap: var(--s3); }
+.wk-podium-row {
+  display: grid;
+  grid-template-columns: 20px minmax(0, 1fr) auto;
+  align-items: center;
+  gap: var(--s4);
+  padding: var(--s3) var(--s4);
+  background: var(--surface-h);
+  border-left: 3px solid var(--wk-team, var(--border-2));
+  border-radius: 4px;
+}
+.wk-podium-pos { font-weight: 700; color: var(--text-2); }
+.wk-podium-code { font-weight: 700; color: var(--wk-team, var(--text)); overflow: hidden; text-overflow: ellipsis; }
+.wk-podium-gap { color: var(--text-2); font-size: 12px; }
+.wk-podium-empty { color: var(--text-3); font-size: 12px; padding: var(--s4); }
+
+.wk-story-card {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s3);
+  padding: var(--s4);
+  background: rgba(230, 36, 41, 0.05);
+  border: 1px solid rgba(230, 36, 41, 0.25);
+  border-radius: 8px;
+}
+.wk-story-label { font-size: 13px; font-weight: 700; color: var(--red); }
+.wk-story-text { font-size: 12px; color: var(--text-2); flex: 1; }
+
+/* ── Next event ── */
+.wk-next-body { display: flex; flex-direction: column; gap: var(--s5); }
+.wk-countdown { display: flex; gap: var(--s5); align-items: baseline; }
+.wk-count-unit { font-size: 13px; color: var(--text-2); font-family: var(--f-mono); }
+.wk-count-unit b { font-size: 40px; color: var(--red); font-weight: 700; margin-right: 2px; }
+.wk-countdown-clock { font-size: 32px; font-weight: 700; color: var(--blue); }
+.wk-countdown-live { font-size: 20px; font-weight: 700; color: var(--red); }
+.wk-next-session { display: flex; flex-direction: column; gap: 2px; }
+.wk-next-label { font-size: 10px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-3); }
+.wk-next-value { font-size: 15px; font-weight: 600; }
+.wk-season-complete-copy { font-size: 13px; color: var(--text-2); }
+
+/* ── Championship impact ── */
+.wk-champ, .wk-briefing, .wk-season-nav {
+  min-width: 0;
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  padding: var(--s5);
+}
+.wk-champ-list { list-style: none; display: flex; flex-direction: column; gap: var(--s3); }
+.wk-champ-row {
+  display: grid;
+  grid-template-columns: 18px minmax(0, 1fr) auto auto;
+  align-items: center;
+  gap: var(--s4);
+  padding: var(--s2) var(--s3);
+  border-left: 3px solid var(--wk-team, var(--border-2));
+}
+.wk-champ-pos { color: var(--text-3); }
+.wk-champ-code { font-weight: 700; color: var(--wk-team, var(--text)); }
+.wk-champ-pts { font-weight: 700; }
+.wk-champ-gap { color: var(--text-3); font-size: 11px; min-width: 34px; text-align: right; }
+.wk-champ-note { margin-top: var(--s4); font-size: 11px; color: var(--text-3); }
+
+/* ── Season progress strip ── */
+.wk-countdown-tbc { font-size: 14px; color: var(--text-3); }
+.wk-season-progress { display: flex; flex-direction: column; gap: var(--s3); }
+.wk-season-progress-head { display: flex; align-items: center; justify-content: space-between; gap: var(--s3); }
+.wk-season-bar {
+  position: relative;
+  height: 8px;
+  border-radius: 999px;
+  background: var(--surface-3);
+  overflow: hidden;
+}
+.wk-season-bar-fill {
+  position: absolute;
+  inset: 0 auto 0 0;
+  background: var(--red);
+  border-radius: 999px;
+}
+.wk-season-progress-label { font-size: 11px; color: var(--text-3); }
+
+/* ── Briefing ── */
+.wk-briefing-list { list-style: none; display: flex; flex-direction: column; }
+.wk-briefing-item { border-top: 1px solid var(--border); }
+.wk-briefing-item:first-child { border-top: none; }
+.wk-briefing-link {
+  display: grid;
+  grid-template-columns: minmax(0, auto) minmax(0, 1fr) auto;
+  align-items: center;
+  gap: var(--s4);
+  padding: var(--s4) 0;
+}
+.wk-briefing-link:hover .wk-briefing-title { color: var(--red); }
+.wk-briefing-cat { font-size: 10px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--red); white-space: nowrap; }
+.wk-briefing-title { font-size: 13px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+.wk-briefing-source { font-size: 11px; color: var(--text-3); white-space: nowrap; }
+
+/* ── Between-sessions / live ── */
+.wk-sessions, .wk-live, .wk-pre { display: flex; flex-direction: column; gap: var(--s5); }
+.wk-sessions-head { display: flex; flex-direction: column; gap: 2px; }
+.wk-sessions-title { font-size: 28px; font-weight: 800; letter-spacing: -0.01em; }
+.wk-sessions-circuit { font-size: 12px; color: var(--text-3); text-transform: uppercase; letter-spacing: 0.06em; }
+
+.wk-timeline {
+  list-style: none;
+  display: flex;
+  gap: var(--s3);
+  overflow-x: auto;
+  padding-bottom: var(--s3);
+  scrollbar-width: thin;
+}
+.wk-timeline-node {
+  flex: 1 0 auto;
+  min-width: 72px;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: var(--s2);
+  padding: var(--s3);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+}
+.wk-timeline-dot { width: 10px; height: 10px; border-radius: 50%; background: var(--surface-3); }
+.wk-timeline-done .wk-timeline-dot { background: var(--green); }
+.wk-timeline-live .wk-timeline-dot { background: var(--red); box-shadow: 0 0 0 3px rgba(230,36,41,0.25); }
+.wk-timeline-next { border-color: var(--red); }
+.wk-timeline-next .wk-timeline-dot { border: 2px solid var(--red); }
+.wk-timeline-name { font-size: 12px; font-weight: 600; }
+.wk-timeline-state { font-size: 9px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-3); }
+.wk-timeline-done .wk-timeline-state { color: var(--green); }
+.wk-timeline-live .wk-timeline-state, .wk-timeline-next .wk-timeline-state { color: var(--red); }
+
+.wk-recap-card, .wk-upnext-card, .wk-live-card {
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  padding: var(--s5);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s4);
+}
+.wk-recap-eyebrow, .wk-upnext-eyebrow { font-size: 10px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--green); }
+.wk-recap-title, .wk-upnext-title { font-size: 20px; font-weight: 700; }
+.wk-upnext-when { font-size: 12px; color: var(--text-3); }
+.wk-upnext-card { border-color: rgba(230,36,41,0.3); }
+
+.wk-live-card { border-color: rgba(230,36,41,0.35); }
+.wk-live-head { display: flex; align-items: center; justify-content: space-between; }
+.wk-live-pulse { width: 12px; height: 12px; border-radius: 50%; background: var(--red); box-shadow: 0 0 0 4px rgba(230,36,41,0.2); }
+.wk-live-lead { font-size: 14px; color: var(--text-2); }
+
+/* ── Pre-session ── */
+.wk-pre-head {
+  display: flex;
+  align-items: center;
+  gap: var(--s5);
+  flex-wrap: wrap;
+}
+.wk-pre-countdown { display: flex; flex-direction: column; gap: 2px; margin-left: auto; }
+.wk-pre-preview { min-width: 0; }
+/* The folded preview page ships its own max-width page; reset it inside Weekend. */
+.wk-pre-preview .preview-page { max-width: 100%; padding: 0; }
+
+/* ── Status views ── */
+.wk-status {
+  max-width: 640px;
+  margin: 64px auto;
+  text-align: center;
+  display: flex;
+  flex-direction: column;
+  gap: var(--s4);
+  align-items: center;
+}
+.wk-status-eyebrow { font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--text-3); }
+.wk-status-title { font-size: 22px; font-weight: 700; }
+.wk-status-sub { font-size: 13px; color: var(--text-2); }
+.wk-status-actions { display: flex; gap: var(--s4); margin-top: var(--s4); }
+.wk-status-error .wk-status-title { color: var(--red); }
+
+/* ── Responsive ── */
+@media (max-width: 900px) {
+  .wk-top-grid, .wk-mid-grid { grid-template-columns: 1fr; }
+  .wk-event-body { grid-template-columns: 1fr; }
+}
+@media (max-width: 640px) {
+  .wk-page { padding: var(--s5) var(--s5) 88px; }
+  .wk-focus {
+    flex-direction: column;
+    align-items: stretch;
+  }
+  .wk-focus-cta { width: 100%; justify-content: center; }
+  .wk-event-name { font-size: 20px; }
+  .wk-sessions-title { font-size: 22px; }
+  .wk-count-unit b { font-size: 32px; }
+  .wk-pre-head { flex-direction: column; align-items: flex-start; }
+  .wk-pre-countdown { margin-left: 0; }
+}
+
+/* ── Explore ── */
+.wk-explore { display: flex; flex-direction: column; gap: var(--s6); }
+.wk-explore-section {
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  padding: var(--s5);
+}
+.wk-explore-grid {
+  list-style: none;
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
+  gap: var(--s4);
+}
+.wk-explore-card {
+  display: flex;
+  flex-direction: column;
+  gap: var(--s2);
+  padding: var(--s4);
+  min-width: 0;
+  background: var(--surface-h);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  height: 100%;
+}
+.wk-explore-card.is-link { transition: border-color 0.12s, background 0.12s; }
+.wk-explore-card.is-link:hover { border-color: var(--text-3); background: var(--surface-2); }
+.wk-explore-top { display: flex; justify-content: space-between; align-items: center; font-size: 11px; color: var(--text-3); }
+.wk-explore-flag { font-size: 18px; }
+.wk-explore-name { font-size: 14px; font-weight: 700; overflow: hidden; text-overflow: ellipsis; }
+.wk-explore-meta { font-size: 11px; color: var(--text-3); }
+.wk-explore-state { font-size: 10px; letter-spacing: 0.08em; text-transform: uppercase; margin-top: var(--s2); }
+.wk-explore-state.is-done { color: var(--green); }
+.wk-explore-state.is-upcoming { color: var(--text-3); }
+
+.wk-explore-drivers { list-style: none; display: flex; flex-wrap: wrap; gap: var(--s3); }
+.wk-driver-chip {
+  display: inline-flex;
+  align-items: center;
+  gap: var(--s3);
+  padding: var(--s3) var(--s4);
+  background: var(--surface-h);
+  border: 1px solid var(--border);
+  border-left: 3px solid var(--wk-team, var(--border-2));
+  border-radius: 6px;
+  transition: border-color 0.12s;
+}
+.wk-driver-chip:hover { border-color: var(--text-3); }
+.wk-driver-pos { color: var(--text-3); font-size: 11px; }
+.wk-driver-code { font-weight: 700; color: var(--wk-team, var(--text)); }
+.wk-driver-pts { color: var(--text-2); font-size: 12px; }
+
+/* ── Reduced motion ── */
+@media (prefers-reduced-motion: reduce) {
+  .wk-cta, .wk-briefing-title, .wk-live-pulse, .wk-timeline-live .wk-timeline-dot { transition: none; }
+}

frontend/src/test/BriefingPage.test.tsx

@@ -0,0 +1,211 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, waitFor, fireEvent, within } from '@testing-library/react'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { BriefingPage } from '../pages/BriefingPage'
+import type { ChampHubDriver, ChampHubTeam, ChampionshipHub, Meeting, NewsItem } from '../types'
+
+vi.mock('../api', () => ({
+  fetchNews: vi.fn(),
+  fetchNewsArticle: vi.fn(),
+  markNewsRead: vi.fn(),
+  fetchSeasons: vi.fn(),
+  fetchSeasonMeetings: vi.fn(),
+  fetchChampionshipHub: vi.fn(),
+}))
+
+import {
+  fetchNews,
+  fetchNewsArticle,
+  fetchSeasons,
+  fetchSeasonMeetings,
+  fetchChampionshipHub,
+  markNewsRead,
+} from '../api'
+
+const mockFetchNews = vi.mocked(fetchNews)
+const mockFetchNewsArticle = vi.mocked(fetchNewsArticle)
+const mockFetchSeasons = vi.mocked(fetchSeasons)
+const mockFetchSeasonMeetings = vi.mocked(fetchSeasonMeetings)
+const mockFetchHub = vi.mocked(fetchChampionshipHub)
+const mockMarkNewsRead = vi.mocked(markNewsRead)
+
+const bahrain: Meeting = {
+  meeting_key: 1,
+  meeting_name: 'Bahrain',
+  meeting_official_name: 'Bahrain GP',
+  location: 'Sakhir',
+  country_name: 'Bahrain',
+  country_code: 'BRN',
+  country_flag: '',
+  circuit_short_name: 'Sakhir',
+  date_start: '2025-03-14T00:00:00+00:00',
+  date_end: '2025-03-16T23:59:59+00:00',
+  year: 2025,
+}
+
+const monaco: Meeting = {
+  meeting_key: 2,
+  meeting_name: 'Monaco',
+  meeting_official_name: 'Monaco GP',
+  location: 'Monaco',
+  country_name: 'Monaco',
+  country_code: 'MON',
+  country_flag: '',
+  circuit_short_name: 'Monaco',
+  date_start: '2025-05-23T00:00:00+00:00',
+  date_end: '2025-05-25T23:59:59+00:00',
+  year: 2025,
+}
+
+const drivers: ChampHubDriver[] = [
+  {
+    driver_number: 1,
+    name_acronym: 'VER',
+    full_name: 'Max Verstappen',
+    team_name: 'Red Bull',
+    team_colour: '3671c6',
+    points: 100,
+    position: 1,
+    wins: 3,
+    podiums: 5,
+    poles: 2,
+    form: [25, 18, 25],
+    cumulative: [25, 43, 68, 100],
+    teammate_wins: 4,
+    teammate_losses: 1,
+    round_positions: [],
+  },
+  {
+    driver_number: 4,
+    name_acronym: 'NOR',
+    full_name: 'Lando Norris',
+    team_name: 'McLaren',
+    team_colour: 'ff8000',
+    points: 80,
+    position: 2,
+    wins: 1,
+    podiums: 4,
+    poles: 1,
+    form: [18, 25, 18],
+    cumulative: [18, 36, 54, 80],
+    teammate_wins: 3,
+    teammate_losses: 2,
+    round_positions: [],
+  },
+]
+
+const teams: ChampHubTeam[] = [
+  { team_name: 'Red Bull', team_colour: '3671c6', points: 150, position: 1, wins: 4 },
+  { team_name: 'McLaren', team_colour: 'ff8000', points: 120, position: 2, wins: 2 },
+]
+
+const hub: ChampionshipHub = {
+  season: 2025,
+  round: 2,
+  total_rounds: 2,
+  rounds_left: 0,
+  last_race: 'Monaco GP',
+  round_labels: ['R1', 'R2'],
+  drivers,
+  teams,
+}
+
+const newsItems: NewsItem[] = [
+  {
+    source: 'autosport-f1',
+    title: 'Verstappen sets the pace in Bahrain',
+    url: 'https://example.com/bahrain-ver',
+    published_at: '2025-03-15T10:00:00Z',
+    fetched_at: '2025-03-15T11:00:00Z',
+    summary: 'Red Bull dominate opening practice',
+  },
+  {
+    source: 'racefans-f1',
+    title: 'Norris targets Monaco upgrade',
+    url: 'https://example.com/monaco-nor',
+    published_at: '2025-04-20T10:00:00Z',
+    fetched_at: '2025-04-20T11:00:00Z',
+    summary: 'McLaren bring new floor',
+  },
+  {
+    source: 'bbc-f1',
+    title: 'Undated paddock rumour',
+    url: 'https://example.com/undated',
+    fetched_at: '2025-04-21T11:00:00Z',
+  },
+]
+
+function renderPage() {
+  const queryClient = new QueryClient({
+    defaultOptions: { queries: { retry: false } },
+  })
+
+  return render(
+    <QueryClientProvider client={queryClient}>
+      <BriefingPage />
+    </QueryClientProvider>,
+  )
+}
+
+describe('BriefingPage digest layout', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    vi.setSystemTime(new Date('2025-04-10T12:00:00Z'))
+    mockFetchSeasons.mockResolvedValue([2025])
+    mockFetchSeasonMeetings.mockResolvedValue([bahrain, monaco])
+    mockFetchHub.mockResolvedValue(hub)
+    mockFetchNews.mockResolvedValue(newsItems)
+    mockFetchNewsArticle.mockResolvedValue({ title: 'Article', content: '<p>Body</p>' })
+    mockMarkNewsRead.mockResolvedValue(undefined)
+  })
+
+  afterEach(() => {
+    vi.useRealTimers()
+  })
+
+  it('renders sticky since-last header, GP sections, and recent bucket', async () => {
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('digest-sticky-header')).toHaveTextContent('Since Bahrain')
+    })
+
+    expect(screen.getByTestId('digest-window-2')).toHaveTextContent('Monaco')
+    expect(screen.getByTestId('digest-window-1')).toHaveTextContent('Bahrain')
+    expect(screen.getByTestId('digest-recent')).toHaveTextContent('Undated paddock rumour')
+    expect(screen.getByText('Verstappen sets the pace in Bahrain')).toBeInTheDocument()
+    expect(screen.getByText('Norris targets Monaco upgrade')).toBeInTheDocument()
+  })
+
+  it('filters the digest when a tag chip is clicked', async () => {
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('digest-sticky-header')).toBeInTheDocument()
+    })
+
+    const sticky = screen.getByTestId('digest-sticky-header')
+    const norTag = within(sticky).getByRole('button', { name: /^NOR$/i })
+    fireEvent.click(norTag)
+
+    await waitFor(() => {
+      expect(screen.queryByText('Verstappen sets the pace in Bahrain')).not.toBeInTheDocument()
+    })
+    expect(screen.getByText('Norris targets Monaco upgrade')).toBeInTheDocument()
+    expect(screen.getByTestId('digest-filter-clear')).toBeInTheDocument()
+
+    fireEvent.click(screen.getByTestId('digest-filter-clear'))
+    await waitFor(() => {
+      expect(screen.getByText('Verstappen sets the pace in Bahrain')).toBeInTheDocument()
+    })
+  })
+
+  it('preserves category tabs', async () => {
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByRole('tab', { name: /All/i })).toBeInTheDocument()
+    })
+    expect(screen.getByRole('tab', { name: /News/i })).toBeInTheDocument()
+  })
+})

frontend/src/test/ChampionshipPage.test.tsx

@@ -29,6 +29,7 @@ function driver(over: Partial<ChampHubDriver>): ChampHubDriver {
     poles: 4,
     form: [25, 18, 25, 15, 25],
     cumulative: [25, 43, 68, 83, 108, 200],
+    round_positions: [1, 2, 1, 3, 1, 1],
     teammate_wins: 9,
     teammate_losses: 1,
     ...over,
@@ -47,6 +48,7 @@ const drivers: ChampHubDriver[] = [
     position: 2,
     wins: 3,
     cumulative: [18, 36, 54, 80, 120, 160],
+    round_positions: [2, 1, 2, 2, 2, 2],
   }),
   driver({
     driver_number: 16,
@@ -58,6 +60,7 @@ const drivers: ChampHubDriver[] = [
     position: 3,
     wins: 1,
     cumulative: [15, 28, 40, 60, 90, 120],
+    round_positions: [3, 3, 3, 0, 3, 3],
   }),
 ]
 
@@ -129,6 +132,22 @@ describe('ChampionshipPage', () => {
     expect(screen.getByText('Cumulative points', { exact: false })).toBeInTheDocument()
   })
 
+  it('switches to the rivalry view with the top two drivers preselected', async () => {
+    renderPage()
+
+    await waitFor(() => expect(screen.getByTestId('championship')).toBeInTheDocument())
+
+    fireEvent.click(screen.getByTestId('champ-tab-rivalry'))
+    expect(screen.getByTestId('champ-view-rivalry')).toBeInTheDocument()
+    // Default pair is the top two in the standings: VER vs NOR.
+    expect(screen.getByTestId('rivalry-pick-a')).toHaveValue('1')
+    expect(screen.getByTestId('rivalry-pick-b')).toHaveValue('4')
+    // VER beats NOR in rounds 1, 3, 5, 6 → 4–2.
+    expect(screen.getByTestId('rivalry-h2h-num')).toHaveTextContent('4–2')
+    expect(screen.getByTestId('rivalry-points-race')).toBeInTheDocument()
+    expect(screen.getByTestId('rivalry-gap')).toBeInTheDocument()
+  })
+
   it('switches to the simulator view and projects standings', async () => {
     renderPage()
 
@@ -150,4 +169,61 @@ describe('ChampionshipPage', () => {
     })
     expect(screen.getByText('No championship data')).toBeInTheDocument()
   })
+
+  it('renders teammate battles section ordered by closest split', async () => {
+    const h2hDrivers: ChampHubDriver[] = [
+      driver({ driver_number: 1, name_acronym: 'VER', team_name: 'Red Bull', points: 200, position: 1 }),
+      driver({
+        driver_number: 4,
+        name_acronym: 'NOR',
+        full_name: 'Lando Norris',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        points: 160,
+        position: 2,
+        teammate_wins: 6,
+        teammate_losses: 5,
+        cumulative: [18, 36, 54, 80, 120, 160],
+      }),
+      driver({
+        driver_number: 81,
+        name_acronym: 'PIA',
+        full_name: 'Oscar Piastri',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        points: 140,
+        position: 3,
+        teammate_wins: 5,
+        teammate_losses: 6,
+        cumulative: [12, 28, 45, 70, 110, 140],
+      }),
+      driver({
+        driver_number: 11,
+        name_acronym: 'PER',
+        full_name: 'Sergio Perez',
+        team_name: 'Red Bull',
+        team_colour: '3671c6',
+        points: 60,
+        position: 4,
+        teammate_wins: 1,
+        teammate_losses: 9,
+        cumulative: [5, 12, 20, 35, 50, 60],
+      }),
+    ]
+    mockFetchHub.mockResolvedValue({ ...hub, drivers: h2hDrivers })
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('champ-teammate-battles')).toBeInTheDocument()
+    })
+
+    expect(screen.getByText('Teammate battles')).toBeInTheDocument()
+    const rows = screen.getAllByTestId('teammate-h2h')
+    expect(rows).toHaveLength(2)
+    // McLaren 6–5 is closer than Red Bull 9–1 — McLaren row first.
+    expect(rows[0]).toHaveTextContent('McLaren')
+    expect(rows[0]).toHaveTextContent('6–5')
+    expect(rows[1]).toHaveTextContent('Red Bull')
+    expect(rows[1]).toHaveTextContent('9–1')
+  })
 })

frontend/src/test/ChampionshipSimulator.test.tsx

@@ -17,6 +17,7 @@ function driver(over: Partial<ChampHubDriver>): ChampHubDriver {
     poles: 0,
     form: [],
     cumulative: [],
+    round_positions: [],
     teammate_wins: 0,
     teammate_losses: 0,
     ...over,

frontend/src/test/ChapterStrip.test.tsx

@@ -0,0 +1,128 @@
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { fireEvent, render, screen } from '@testing-library/react'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { ChapterStrip } from '../components/ChapterStrip'
+import type { Chapter } from '../types'
+
+const chapters: Chapter[] = [
+  {
+    kind: 'start',
+    title: 'Start',
+    headline: 'Lights out — the field charges into Turn 1',
+    start_lap: 1,
+    end_lap: 1,
+    start_time: '2025-05-25T13:00:00Z',
+    end_time: '2025-05-25T13:01:00Z',
+    driver_numbers: [],
+  },
+  {
+    kind: 'safety_car',
+    title: 'Safety Car (L12-L15)',
+    headline: 'Sainz incident brings out the Safety Car — leaders dive for the pits',
+    start_lap: 12,
+    end_lap: 15,
+    start_time: '2025-05-25T13:12:00Z',
+    end_time: '2025-05-25T13:15:00Z',
+    driver_numbers: [55],
+  },
+]
+
+const tMin = new Date('2025-05-25T13:00:00Z').getTime()
+const tMax = new Date('2025-05-25T13:20:00Z').getTime()
+const tRange = tMax - tMin
+
+function renderStrip(
+  overrides: Partial<{
+    scrubTime: number | null
+    onChapterClick: (index: number, scrub: number) => void
+  }> = {},
+) {
+  const onChapterClick = overrides.onChapterClick ?? vi.fn()
+  const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+  render(
+    <QueryClientProvider client={queryClient}>
+      <ChapterStrip
+        chapters={chapters}
+        scrubTime={overrides.scrubTime ?? null}
+        tMin={tMin}
+        tRange={tRange}
+        tourActive={false}
+        tourChapterIndex={null}
+        onChapterClick={onChapterClick}
+        onTourToggle={vi.fn()}
+      />
+    </QueryClientProvider>,
+  )
+  return { onChapterClick }
+}
+
+describe('ChapterStrip', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('renders chapter headlines and lap ranges', () => {
+    renderStrip()
+    expect(screen.getByTestId('chapter-strip')).toBeInTheDocument()
+    expect(screen.getByText('Lights out — the field charges into Turn 1')).toBeInTheDocument()
+    expect(screen.getByText('L12–L15')).toBeInTheDocument()
+  })
+
+  it('renders an empty-state card when there are no chapters', () => {
+    const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+    render(
+      <QueryClientProvider client={queryClient}>
+        <ChapterStrip
+          chapters={[]}
+          scrubTime={null}
+          tMin={tMin}
+          tRange={tRange}
+          tourActive={false}
+          tourChapterIndex={null}
+          onChapterClick={vi.fn()}
+          onTourToggle={vi.fn()}
+        />
+      </QueryClientProvider>,
+    )
+    expect(screen.getByTestId('chapter-strip-empty')).toBeInTheDocument()
+  })
+
+  it('highlights the active chapter from scrub time', () => {
+    const scrub = (new Date('2025-05-25T13:13:00Z').getTime() - tMin) / tRange
+    renderStrip({ scrubTime: scrub })
+    expect(screen.getByTestId('chapter-card-1')).toHaveClass('active')
+    expect(screen.getByTestId('chapter-card-0')).not.toHaveClass('active')
+  })
+
+  it('calls click handler to jump scrubber', () => {
+    const onChapterClick = vi.fn<(index: number, scrub: number) => void>()
+    renderStrip({ onChapterClick })
+    fireEvent.click(screen.getByTestId('chapter-card-1'))
+    expect(onChapterClick).toHaveBeenCalledTimes(1)
+    const [index, scrub] = onChapterClick.mock.calls[0]
+    expect(index).toBe(1)
+    expect(scrub).toBeCloseTo(0.6, 2)
+  })
+
+  it('highlights an explicitly selected chapter even when scrub is outside its raw window', () => {
+    // Scrub parked at chart start; chapter 1's raw times are mid-race, but selection wins.
+    const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+    render(
+      <QueryClientProvider client={queryClient}>
+        <ChapterStrip
+          chapters={chapters}
+          scrubTime={0}
+          tMin={tMin}
+          tRange={tRange}
+          tourActive={false}
+          tourChapterIndex={null}
+          selectedChapterIndex={1}
+          onChapterClick={vi.fn()}
+          onTourToggle={vi.fn()}
+        />
+      </QueryClientProvider>,
+    )
+    expect(screen.getByTestId('chapter-card-1')).toHaveClass('active')
+    expect(screen.getByTestId('chapter-card-0')).not.toHaveClass('active')
+  })
+})

frontend/src/test/CommandCenterPage.test.tsx

@@ -1,244 +0,0 @@
-import { describe, it, expect, vi, beforeEach } from 'vitest'
-import { render, screen, waitFor } from '@testing-library/react'
-import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
-import { RouterProvider, createRouter, createRootRoute, createRoute } from '@tanstack/react-router'
-import { CommandCenterPage } from '../pages/CommandCenterPage'
-import type { DatasetInfo, Meeting, Weekend } from '../types'
-
-vi.mock('../api', () => ({
-  fetchSeasons: vi.fn(),
-  fetchLocalMeetings: vi.fn(),
-  fetchSeasonMeetings: vi.fn(),
-  fetchSessions: vi.fn(),
-  fetchWeekend: vi.fn(),
-  fetchLiveState: vi.fn(),
-  fetchChampionshipHub: vi.fn(),
-  fetchRaceHub: vi.fn(),
-}))
-
-import {
-  fetchSeasons,
-  fetchLocalMeetings,
-  fetchSeasonMeetings,
-  fetchSessions,
-  fetchWeekend,
-  fetchLiveState,
-  fetchChampionshipHub,
-  fetchRaceHub,
-} from '../api'
-
-const mockFetchSeasons = vi.mocked(fetchSeasons)
-const mockFetchLocalMeetings = vi.mocked(fetchLocalMeetings)
-const mockFetchSeasonMeetings = vi.mocked(fetchSeasonMeetings)
-const mockFetchSessions = vi.mocked(fetchSessions)
-const mockFetchWeekend = vi.mocked(fetchWeekend)
-const mockFetchLiveState = vi.mocked(fetchLiveState)
-const mockFetchChampionshipHub = vi.mocked(fetchChampionshipHub)
-const mockFetchRaceHub = vi.mocked(fetchRaceHub)
-
-const meeting: Meeting = {
-  meeting_key: 1229,
-  meeting_name: 'Monaco',
-  meeting_official_name: 'FORMULA 1 GRAND PRIX DE MONACO 2025',
-  location: 'Monaco',
-  country_name: 'Monaco',
-  country_code: 'MON',
-  country_flag: '',
-  circuit_short_name: 'Monaco',
-  date_start: '2025-05-23T00:00:00+00:00',
-  date_end: '2025-05-25T00:00:00+00:00',
-  year: 2025,
-}
-
-const fullDatasets: Record<string, DatasetInfo> = {
-  meeting: { status: 'available', source: 'local', count: 1 },
-  session: { status: 'available', source: 'local', count: 1 },
-  drivers: { status: 'available', source: 'local', count: 20 },
-  results: { status: 'available', source: 'local', count: 20 },
-  starting_grid: { status: 'available', source: 'local', count: 20 },
-  stints: { status: 'available', source: 'local', count: 2 },
-  pit_stops: { status: 'available', source: 'local', count: 1 },
-  positions: { status: 'available', source: 'local', count: 3 },
-  race_control: { status: 'available', source: 'local', count: 1 },
-  weather: { status: 'available', source: 'local', count: 1 },
-  laps: { status: 'available', source: 'local', count: 1 },
-}
-
-const weekend: Weekend = {
-  source: 'local',
-  meeting_key: 1229,
-  meeting,
-  default_session_key: 9472,
-  sessions: [
-    {
-      session: {
-        session_key: 9472,
-        session_name: 'Race',
-        session_type: 'Race',
-        meeting_key: 1229,
-        date_start: '2025-05-25T13:00:00+00:00',
-        date_end: '2025-05-25T15:00:00+00:00',
-        gmt_offset: '02:00:00',
-      },
-      source: 'local',
-      datasets: fullDatasets,
-    },
-  ],
-}
-
-function renderPage() {
-  const queryClient = new QueryClient({
-    defaultOptions: { queries: { retry: false } },
-  })
-
-  const rootRoute = createRootRoute({
-    component: () => (
-      <QueryClientProvider client={queryClient}>
-        <CommandCenterPage />
-      </QueryClientProvider>
-    ),
-  })
-
-  const indexRoute = createRoute({
-    getParentRoute: () => rootRoute,
-    path: '/',
-    component: CommandCenterPage,
-  })
-
-  const router = createRouter({ routeTree: rootRoute.addChildren([indexRoute]) })
-
-  return render(<RouterProvider router={router} />)
-}
-
-describe('CommandCenterPage', () => {
-  beforeEach(() => {
-    vi.clearAllMocks()
-    mockFetchLiveState.mockResolvedValue({ is_live: false, data: null })
-    mockFetchSessions.mockResolvedValue([])
-    mockFetchChampionshipHub.mockResolvedValue({
-      season: 2025,
-      round: 1,
-      total_rounds: 1,
-      rounds_left: 0,
-      last_race: 'Monaco',
-      round_labels: ['R1'],
-      drivers: [],
-      teams: [],
-    })
-    mockFetchRaceHub.mockResolvedValue({
-      source: 'local',
-      session_key: 9472,
-      datasets: fullDatasets,
-      results: [
-        {
-          driver_number: 1,
-          position: 1,
-          name_acronym: 'VER',
-          full_name: 'Max Verstappen',
-          team_name: 'Red Bull Racing',
-          team_colour: '3671c6',
-          dnf: false,
-          dns: false,
-          dsq: false,
-          duration: 7200,
-          gap_to_leader: null,
-          number_of_laps: 78,
-          points: 25,
-          session_key: 9472,
-          meeting_key: 1229,
-        },
-      ],
-      starting_grid: [],
-      drivers: [],
-      stints: [],
-      pit_stops: [],
-      positions: [],
-      race_control: [],
-      weather: [],
-      laps: [],
-    })
-  })
-
-  it('shows empty state when no seasons are ingested', async () => {
-    mockFetchSeasons.mockResolvedValue([])
-
-    renderPage()
-
-    await waitFor(() => {
-      expect(screen.getByTestId('command-center-empty')).toBeInTheDocument()
-    })
-    expect(screen.getByText('No local data yet')).toBeInTheDocument()
-  })
-
-  it('shows weekend identity band and schedule when data exists', async () => {
-    mockFetchSeasons.mockResolvedValue([2025])
-    mockFetchLocalMeetings.mockResolvedValue([meeting])
-    mockFetchSeasonMeetings.mockResolvedValue([meeting])
-    mockFetchWeekend.mockResolvedValue(weekend)
-
-    renderPage()
-
-    await waitFor(() => {
-      expect(screen.getByTestId('command-center')).toBeInTheDocument()
-    })
-
-    await waitFor(() => {
-      expect(screen.getByTestId('cc-session-9472')).toBeInTheDocument()
-    })
-    expect(screen.getByTestId('cc-focus')).toHaveTextContent('Monaco')
-    expect(screen.getByTestId('cc-season-calendar')).toHaveTextContent('Season Calendar')
-    expect(screen.getByTestId('cc-calendar-1229')).toHaveTextContent('R01')
-    expect(screen.getByText('No live session')).toBeInTheDocument()
-    expect(screen.getByTestId('hero-last-race-link')).toHaveTextContent('Monaco')
-  })
-
-  it('uses OpenF1 calendar metadata to focus the current weekend when local ingest is behind', async () => {
-    const canada = {
-      ...meeting,
-      meeting_key: 1301,
-      meeting_name: 'Canada',
-      country_name: 'Canada',
-      country_code: 'CAN',
-      circuit_short_name: 'Montreal',
-      date_start: '2026-05-22T00:00:00+00:00',
-      date_end: '2026-05-24T23:59:59+00:00',
-      year: 2026,
-    }
-    const monaco = {
-      ...meeting,
-      meeting_key: 1302,
-      meeting_name: 'Monaco',
-      date_start: '2026-06-05T00:00:00+00:00',
-      date_end: '2026-06-07T23:59:59+00:00',
-      year: 2026,
-    }
-
-    vi.setSystemTime(new Date('2026-06-06T15:15:00Z'))
-    mockFetchSeasons.mockResolvedValue([2026])
-    mockFetchLocalMeetings.mockResolvedValue([canada])
-    mockFetchSeasonMeetings.mockResolvedValue([canada, monaco])
-    mockFetchWeekend.mockResolvedValue({ ...weekend, meeting: canada, meeting_key: canada.meeting_key })
-    mockFetchSessions.mockResolvedValue([
-      {
-        session_key: 9602,
-        session_name: 'Qualifying',
-        session_type: 'Qualifying',
-        meeting_key: monaco.meeting_key,
-        date_start: '2026-06-06T15:00:00+00:00',
-        date_end: '2026-06-06T16:00:00+00:00',
-        gmt_offset: '02:00:00',
-      },
-    ])
-
-    renderPage()
-
-    await waitFor(() => {
-      expect(screen.getByTestId('cc-focus')).toHaveTextContent('Monaco')
-    })
-    expect(screen.getByTestId('cc-focus')).toHaveTextContent('Live now')
-    expect(screen.getByTestId('cc-session-9602')).toHaveTextContent('On track')
-    expect(screen.getByTestId('hero-live-link')).toHaveAttribute('href', '/live')
-
-    vi.useRealTimers()
-  })
-})

frontend/src/test/DriverProfilePage.test.tsx

@@ -0,0 +1,160 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, waitFor } from '@testing-library/react'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { RouterProvider, createRouter, createRootRoute, createRoute } from '@tanstack/react-router'
+import { DriverProfilePage } from '../pages/DriverProfilePage'
+import type { DriverSummary } from '../types'
+
+vi.mock('../api', () => ({
+  fetchSeasons: vi.fn(),
+  fetchDriverSummary: vi.fn(),
+}))
+
+import { fetchSeasons, fetchDriverSummary } from '../api'
+
+const mockFetchSeasons = vi.mocked(fetchSeasons)
+const mockFetchSummary = vi.mocked(fetchDriverSummary)
+
+const summary: DriverSummary = {
+  season: 2025,
+  driver_number: 1,
+  name_acronym: 'VER',
+  full_name: 'Max Verstappen',
+  team_name: 'Red Bull',
+  team_colour: '3671c6',
+  headshot_url: '',
+  points: 50,
+  position: 1,
+  wins: 2,
+  podiums: 2,
+  poles: 1,
+  form: [25, 25],
+  cumulative: [25, 50],
+  round_labels: ['R1', 'R2'],
+  rounds: [
+    {
+      meeting_key: 1201,
+      meeting_name: 'Bahrain Grand Prix',
+      country_code: 'BHR',
+      country_name: 'Bahrain',
+      race_position: 1,
+      grid_position: 1,
+      quali_position: 1,
+      points: 25,
+      dnf: false,
+      dns: false,
+      dsq: false,
+    },
+    {
+      meeting_key: 1202,
+      meeting_name: 'Saudi Arabian Grand Prix',
+      country_code: 'SAU',
+      country_name: 'Saudi Arabia',
+      race_position: 1,
+      grid_position: 4,
+      quali_position: 4,
+      points: 25,
+      dnf: false,
+      dns: false,
+      dsq: false,
+    },
+  ],
+}
+
+function renderPage(props: { driverNumber: number; year?: number }) {
+  const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+  const rootRoute = createRootRoute({
+    component: () => (
+      <QueryClientProvider client={queryClient}>
+        <DriverProfilePage driverNumber={props.driverNumber} year={props.year} />
+      </QueryClientProvider>
+    ),
+  })
+  const indexRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/',
+    component: () => null,
+  })
+  const router = createRouter({ routeTree: rootRoute.addChildren([indexRoute]) })
+  return render(<RouterProvider router={router} />)
+}
+
+describe('DriverProfilePage', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockFetchSeasons.mockResolvedValue([2025])
+    mockFetchSummary.mockResolvedValue(summary)
+  })
+
+  it('renders header, form, quali-vs-race, and rounds sections', async () => {
+    renderPage({ driverNumber: 1, year: 2025 })
+
+    await waitFor(() => {
+      expect(screen.getByTestId('driver-profile')).toBeInTheDocument()
+    })
+
+    // Header: identity + season stats.
+    expect(screen.getByTestId('dp-header')).toBeInTheDocument()
+    expect(screen.getByText('Max Verstappen')).toBeInTheDocument()
+    expect(screen.getByText('#1')).toBeInTheDocument()
+    expect(screen.getByText('Red Bull', { exact: false })).toBeInTheDocument()
+    // 'P1' / '50' also appear in the rounds table and chart axis.
+    expect(screen.getAllByText('P1').length).toBeGreaterThan(0)
+    expect(screen.getAllByText('50').length).toBeGreaterThan(0)
+
+    // Season form strip.
+    expect(screen.getByTestId('dp-form')).toBeInTheDocument()
+    expect(screen.getByText('Cumulative points')).toBeInTheDocument()
+
+    // Quali-vs-race chart shows the delta from the Saudi round (P4 → P1 = +3).
+    expect(screen.getByTestId('dp-quali-race')).toBeInTheDocument()
+    expect(screen.getAllByText('+3').length).toBeGreaterThan(0)
+
+    // Track-by-track table rows with flags.
+    const rounds = screen.getByTestId('dp-rounds')
+    expect(rounds).toBeInTheDocument()
+    expect(screen.getByText('Bahrain Grand Prix')).toBeInTheDocument()
+    expect(screen.getByText('Saudi Arabian Grand Prix')).toBeInTheDocument()
+    expect(rounds.textContent).toContain('🇧🇭')
+    expect(rounds.textContent).toContain('🇸🇦')
+
+    // With an explicit year, the seasons list is not needed.
+    expect(mockFetchSeasons).not.toHaveBeenCalled()
+    expect(mockFetchSummary).toHaveBeenCalledWith(1, 2025)
+  })
+
+  it('defaults to the latest season when no year is given', async () => {
+    renderPage({ driverNumber: 1 })
+
+    await waitFor(() => {
+      expect(screen.getByTestId('driver-profile')).toBeInTheDocument()
+    })
+    expect(mockFetchSummary).toHaveBeenCalledWith(1, 2025)
+  })
+
+  it('shows the API error message on failure', async () => {
+    mockFetchSummary.mockRejectedValue(new Error('API 404: Not Found'))
+    renderPage({ driverNumber: 99, year: 2025 })
+
+    await waitFor(() => {
+      expect(screen.getByText('API 404: Not Found')).toBeInTheDocument()
+    })
+  })
+
+  it('shows empty states when no rounds are completed', async () => {
+    mockFetchSummary.mockResolvedValue({
+      ...summary,
+      form: [],
+      cumulative: [],
+      round_labels: [],
+      rounds: [],
+    })
+    renderPage({ driverNumber: 1, year: 2025 })
+
+    await waitFor(() => {
+      expect(screen.getByTestId('driver-profile')).toBeInTheDocument()
+    })
+    expect(screen.getAllByText('No completed rounds yet.').length).toBe(2)
+    expect(screen.getByText('No grid-vs-finish data yet.')).toBeInTheDocument()
+  })
+})

frontend/src/test/Nav.test.tsx

@@ -0,0 +1,67 @@
+import { describe, it, expect } from 'vitest'
+import { render, screen, waitFor, within } from '@testing-library/react'
+import {
+  Outlet,
+  RouterProvider,
+  createRouter,
+  createRootRoute,
+  createRoute,
+  createMemoryHistory,
+} from '@tanstack/react-router'
+import { Nav } from '../components/Nav'
+
+function renderNav() {
+  const rootRoute = createRootRoute({
+    component: () => (
+      <>
+        <Nav />
+        <Outlet />
+      </>
+    ),
+  })
+  const stub = (p: string, id: string) =>
+    createRoute({ getParentRoute: () => rootRoute, path: p, component: () => <div data-testid={id} /> })
+  const router = createRouter({
+    routeTree: rootRoute.addChildren([
+      stub('/', 'home'),
+      stub('/championship', 'championship'),
+      stub('/briefing', 'briefing'),
+      stub('/explore', 'explore'),
+      stub('/admin', 'admin'),
+    ]),
+    history: createMemoryHistory({ initialEntries: ['/'] }),
+  })
+  return render(<RouterProvider router={router} />)
+}
+
+const DESTINATIONS = ['Weekend', 'Championship', 'Briefing', 'Explore']
+
+describe('Nav — one primary navigation system per breakpoint', () => {
+  it('exposes exactly two Primary landmarks (one per breakpoint), never more', async () => {
+    renderNav()
+    await waitFor(() => expect(screen.getAllByRole('navigation', { name: 'Primary' })).toHaveLength(2))
+  })
+
+  it('every Primary landmark contains all four destinations', async () => {
+    renderNav()
+    await waitFor(() => expect(screen.getAllByRole('navigation', { name: 'Primary' }).length).toBe(2))
+    const primaries = screen.getAllByRole('navigation', { name: 'Primary' })
+    for (const nav of primaries) {
+      for (const label of DESTINATIONS) {
+        expect(within(nav).getByRole('link', { name: new RegExp(`^${label}$`) })).toBeInTheDocument()
+      }
+    }
+  })
+
+  it('keeps Admin out of every Primary landmark (operator utility only)', async () => {
+    renderNav()
+    await waitFor(() => expect(screen.getAllByRole('navigation', { name: 'Primary' }).length).toBe(2))
+    const primaries = screen.getAllByRole('navigation', { name: 'Primary' })
+    for (const nav of primaries) {
+      expect(within(nav).queryByRole('link', { name: /Admin/i })).not.toBeInTheDocument()
+    }
+    // Admin lives in the operator utilities toolbar.
+    const toolbar = screen.getByRole('toolbar', { name: 'Operator utilities' })
+    expect(within(toolbar).getByRole('link', { name: /Admin/i })).toBeInTheDocument()
+  })
+})

frontend/src/test/RaceHubPage.test.tsx

@@ -1,4 +1,4 @@
-import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
 import { render, screen, waitFor, fireEvent } from '@testing-library/react'
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
 import {
@@ -9,21 +9,38 @@ import {
   createRoute,
 } from '@tanstack/react-router'
 import { RaceHubPage } from '../pages/RaceHubPage'
-import type { DatasetInfo, Meeting, RaceHub, Session, Weekend } from '../types'
+import type {
+  DatasetInfo,
+  Meeting,
+  RaceHub,
+  Session,
+  Weekend,
+  WeekendContext,
+} from '../types'
 
 vi.mock('../api', () => ({
   fetchRaceHub: vi.fn(),
   fetchSeasons: vi.fn(),
   fetchLocalMeetings: vi.fn(),
   fetchWeekend: vi.fn(),
+  fetchWeekendContext: vi.fn(),
 }))
 
-import { fetchRaceHub, fetchSeasons, fetchLocalMeetings, fetchWeekend } from '../api'
+import {
+  fetchRaceHub,
+  fetchSeasons,
+  fetchLocalMeetings,
+  fetchWeekend,
+  fetchWeekendContext,
+} from '../api'
 
 const mockFetchRaceHub = vi.mocked(fetchRaceHub)
 const mockFetchSeasons = vi.mocked(fetchSeasons)
 const mockFetchLocalMeetings = vi.mocked(fetchLocalMeetings)
 const mockFetchWeekend = vi.mocked(fetchWeekend)
+const mockFetchWeekendContext = vi.mocked(fetchWeekendContext)
+
+const NOW = new Date('2025-06-01T00:00:00Z')
 
 const meeting: Meeting = {
   meeting_key: 1229,
@@ -59,6 +76,16 @@ const qualSession: Session = {
   gmt_offset: '02:00:00',
 }
 
+const futureSession: Session = {
+  session_key: 9600,
+  session_name: 'Race',
+  session_type: 'Race',
+  meeting_key: 1300,
+  date_start: '2099-05-25T13:00:00+00:00',
+  date_end: '2099-05-25T15:00:00+00:00',
+  gmt_offset: '02:00:00',
+}
+
 const fullDatasets: Record<string, DatasetInfo> = {
   meeting: { status: 'available', source: 'local', count: 1 },
   session: { status: 'available', source: 'local', count: 1 },
@@ -155,6 +182,7 @@ const raceHub: RaceHub = {
       is_pit_out_lap: false,
     },
   ],
+  chapters: [],
 }
 
 const weekend: Weekend = {
@@ -168,6 +196,41 @@ const weekend: Weekend = {
   ],
 }
 
+const weekendContext: WeekendContext = {
+  season: 2025,
+  temporal_state: 'post_weekend',
+  focus_meeting: meeting,
+  previous_meeting: meeting,
+  default_analysis_session: {
+    session: raceSession,
+    meeting,
+    availability: {
+      schedule: 'available',
+      live_transport: 'unknown',
+      live_session: 'inactive',
+      archive: 'unavailable',
+      local_analysis: 'complete',
+      freshness: 'fresh',
+      limitations: [],
+    },
+  },
+  previous_completed_session: {
+    session: raceSession,
+    meeting,
+    availability: {
+      schedule: 'available',
+      live_transport: 'unknown',
+      live_session: 'inactive',
+      archive: 'unavailable',
+      local_analysis: 'complete',
+      freshness: 'fresh',
+      limitations: [],
+    },
+  },
+  championship_round: 8,
+  total_championship_rounds: 24,
+}
+
 function renderRaceHub(sessionKey: number) {
   const queryClient = new QueryClient({
     defaultOptions: { queries: { retry: false } },
@@ -180,6 +243,19 @@ function renderRaceHub(sessionKey: number) {
       </QueryClientProvider>
     ),
   })
+  const weekendRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/',
+    validateSearch: (search: Record<string, unknown>) => {
+      const meetingKey = Number(search.meeting_key)
+      const sk = Number(search.session_key)
+      return {
+        ...(Number.isFinite(meetingKey) && meetingKey > 0 ? { meeting_key: meetingKey } : {}),
+        ...(Number.isFinite(sk) && sk > 0 ? { session_key: sk } : {}),
+      }
+    },
+    component: () => <div data-testid="weekend-stub" />,
+  })
   const raceHubRoute = createRoute({
     getParentRoute: () => rootRoute,
     path: '/race-hub',
@@ -193,11 +269,10 @@ function renderRaceHub(sessionKey: number) {
     },
   })
   const router = createRouter({
-    routeTree: rootRoute.addChildren([raceHubRoute]),
+    routeTree: rootRoute.addChildren([weekendRoute, raceHubRoute]),
     history: undefined,
   })
 
-  // Navigate to the URL before mounting
   router.navigate({ to: '/race-hub', search: sessionKey ? { session_key: sessionKey } : {} })
   return render(<RouterProvider router={router} />)
 }
@@ -205,10 +280,17 @@ function renderRaceHub(sessionKey: number) {
 describe('RaceHubPage', () => {
   beforeEach(() => {
     vi.clearAllMocks()
+    vi.useFakeTimers({ shouldAdvanceTime: true })
+    vi.setSystemTime(NOW)
     mockFetchSeasons.mockResolvedValue([2025])
     mockFetchLocalMeetings.mockResolvedValue([meeting])
     mockFetchWeekend.mockResolvedValue(weekend)
     mockFetchRaceHub.mockResolvedValue(raceHub)
+    mockFetchWeekendContext.mockResolvedValue(weekendContext)
+  })
+
+  afterEach(() => {
+    vi.useRealTimers()
   })
 
   it('renders the workspace identity band, session rail, and overview for a known session', async () => {
@@ -223,9 +305,9 @@ describe('RaceHubPage', () => {
     )
     expect(screen.getByTestId('rh-session-9471')).toBeInTheDocument()
 
-    // Overview is default
     expect(screen.getByTestId('rh-overview')).toBeInTheDocument()
     expect(screen.getByText('Winner')).toBeInTheDocument()
+    expect(screen.queryByText('Local Coverage')).not.toBeInTheDocument()
   })
 
   it('exposes Race Story sub-controls for classification, grid, and positions', async () => {
@@ -235,17 +317,43 @@ describe('RaceHubPage', () => {
     fireEvent.click(screen.getByRole('tab', { name: 'Race Story' }))
 
     expect(screen.getByText('VER')).toBeInTheDocument()
-    
   })
 
-  it('keeps Data Status accessible and free of inline CLI guidance', async () => {
+  it('keeps Diagnostics accessible behind a secondary action, free of inline CLI guidance', async () => {
     renderRaceHub(9472)
     await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
 
-    fireEvent.click(screen.getByRole('tab', { name: 'Data Status' }))
+    fireEvent.click(screen.getByRole('tab', { name: 'Diagnostics' }))
 
     expect(screen.getByTestId('rh-data-status')).toBeInTheDocument()
     expect(screen.queryByText(/ingest-session/i)).not.toBeInTheDocument()
+
+    expect(screen.queryByTestId('rh-dataset-strip')).not.toBeInTheDocument()
+    fireEvent.click(screen.getByTestId('rh-diagnostics-toggle'))
+    expect(screen.getByTestId('rh-dataset-strip')).toBeInTheDocument()
+  })
+
+  it('does not render the raw dataset strip before fan-facing content', async () => {
+    renderRaceHub(9472)
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+
+    expect(screen.getByTestId('rh-overview')).toBeInTheDocument()
+    expect(screen.queryByTestId('rh-dataset-strip')).not.toBeInTheDocument()
+  })
+
+  it('groups analysis navigation into Story, Analysis, and Data & Context', async () => {
+    renderRaceHub(9472)
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+
+    expect(screen.getByTestId('rh-tabgroup-story')).toBeInTheDocument()
+    expect(screen.getByTestId('rh-tabgroup-analysis')).toBeInTheDocument()
+    expect(screen.getByTestId('rh-tabgroup-context')).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Overview' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Strategy' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Compare' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Lap Data' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Race Control' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Diagnostics' })).toBeInTheDocument()
   })
 
   it('toggles the inline weekend switcher', async () => {
@@ -255,4 +363,213 @@ describe('RaceHubPage', () => {
     fireEvent.click(screen.getByTestId('rh-switch-weekend'))
     expect(await screen.findByTestId('rh-switcher')).toBeInTheDocument()
   })
+
+  it('resolves bare /race-hub through canonical Weekend Context default analysis', async () => {
+    mockFetchWeekendContext.mockResolvedValue({
+      ...weekendContext,
+      default_analysis_session: {
+        session: qualSession,
+        meeting,
+        availability: {
+          schedule: 'available',
+          live_transport: 'unknown',
+          live_session: 'inactive',
+          archive: 'unavailable',
+          local_analysis: 'complete',
+          freshness: 'fresh',
+          limitations: [],
+        },
+      },
+    })
+
+    renderRaceHub(0)
+
+    await waitFor(() => expect(mockFetchRaceHub).toHaveBeenCalledWith(9471))
+    expect(mockFetchRaceHub).not.toHaveBeenCalledWith(9600)
+  })
+
+  it('shows no-analysis fallback when Weekend Context has no default analysis', async () => {
+    mockFetchWeekendContext.mockResolvedValue({
+      ...weekendContext,
+      default_analysis_session: undefined,
+      previous_completed_session: undefined,
+    })
+
+    renderRaceHub(0)
+
+    await waitFor(() => expect(screen.getByTestId('race-hub-no-analysis')).toBeInTheDocument())
+    expect(mockFetchRaceHub).not.toHaveBeenCalled()
+  })
+
+  it('renders a pre-session view instead of empty analysis for a future session', async () => {
+    mockFetchRaceHub.mockResolvedValue({
+      ...raceHub,
+      session_key: 9600,
+      source: 'none',
+      session: futureSession,
+      meeting: { ...meeting, meeting_key: 1300 },
+      results: [],
+      starting_grid: [],
+      datasets: {},
+    })
+    mockFetchWeekend.mockResolvedValue({
+      source: 'none',
+      meeting_key: 1300,
+      meeting: { ...meeting, meeting_key: 1300 },
+      sessions: [{ session: futureSession, source: 'none', datasets: {} }],
+    })
+
+    renderRaceHub(9600)
+
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+    expect(await screen.findByTestId('rh-presession')).toBeInTheDocument()
+    expect(screen.queryByTestId('rh-overview')).not.toBeInTheDocument()
+    expect(screen.queryByText('Winner')).not.toBeInTheDocument()
+  })
+
+  it('renders a preparing view for a settling session with no local analysis', async () => {
+    mockFetchWeekend.mockResolvedValue({
+      ...weekend,
+      sessions: [
+        { session: raceSession, source: 'none', datasets: {} },
+      ],
+    })
+    mockFetchWeekendContext.mockResolvedValue({
+      ...weekendContext,
+      temporal_state: 'session_settling',
+      default_analysis_session: undefined,
+      previous_completed_session: {
+        session: raceSession,
+        meeting,
+        availability: {
+          schedule: 'available',
+          live_transport: 'unknown',
+          live_session: 'inactive',
+          archive: 'unavailable',
+          local_analysis: 'pending',
+          freshness: 'fresh',
+          limitations: [],
+        },
+      },
+    })
+    mockFetchRaceHub.mockResolvedValue({
+      ...raceHub,
+      source: 'none',
+      results: [],
+      starting_grid: [],
+      datasets: {},
+    })
+
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('rh-preparing')).toBeInTheDocument())
+    expect(screen.queryByTestId('rh-overview')).not.toBeInTheDocument()
+  })
+
+  it('renders unavailable distinctly from request errors', async () => {
+    mockFetchWeekend.mockResolvedValue({
+      ...weekend,
+      sessions: [{ session: raceSession, source: 'none', datasets: {} }],
+    })
+    mockFetchWeekendContext.mockResolvedValue({
+      ...weekendContext,
+      previous_completed_session: {
+        session: raceSession,
+        meeting,
+        availability: {
+          schedule: 'available',
+          live_transport: 'unknown',
+          live_session: 'inactive',
+          archive: 'unavailable',
+          local_analysis: 'unavailable',
+          freshness: 'stale',
+          limitations: ['analysis_blocked'],
+        },
+      },
+      default_analysis_session: {
+        session: raceSession,
+        meeting,
+        availability: {
+          schedule: 'available',
+          live_transport: 'unknown',
+          live_session: 'inactive',
+          archive: 'unavailable',
+          local_analysis: 'unavailable',
+          freshness: 'stale',
+          limitations: ['analysis_blocked'],
+        },
+      },
+    })
+    mockFetchRaceHub.mockResolvedValue({
+      ...raceHub,
+      source: 'none',
+      results: [],
+      datasets: {},
+    })
+
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('rh-unavailable')).toBeInTheDocument())
+    expect(screen.queryByTestId('race-hub-error')).not.toBeInTheDocument()
+  })
+
+  it('labels a completed but partial session as Partial and keeps analysis', async () => {
+    mockFetchWeekend.mockResolvedValue({
+      ...weekend,
+      sessions: [
+        { session: qualSession, source: 'local', datasets: fullDatasets },
+        { session: raceSession, source: 'partial', datasets: { drivers: fullDatasets.drivers } },
+      ],
+    })
+    mockFetchWeekendContext.mockResolvedValue({
+      ...weekendContext,
+      default_analysis_session: {
+        session: raceSession,
+        meeting,
+        availability: {
+          schedule: 'available',
+          live_transport: 'unknown',
+          live_session: 'inactive',
+          archive: 'unavailable',
+          local_analysis: 'partial',
+          freshness: 'fresh',
+          limitations: [],
+        },
+      },
+    })
+
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('rh-active-state')).toBeInTheDocument())
+    expect(screen.getByTestId('rh-active-state')).toHaveTextContent('Partial')
+    expect(screen.getByTestId('rh-partial-banner')).toBeInTheDocument()
+    expect(screen.getByTestId('rh-overview')).toBeInTheDocument()
+  })
+
+  it('offers retry and back-to-Weekend on an error', async () => {
+    mockFetchRaceHub.mockRejectedValue(new Error('boom'))
+
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('race-hub-error')).toBeInTheDocument())
+    expect(screen.getByTestId('rh-retry')).toBeInTheDocument()
+    const back = screen.getByTestId('rh-back-weekend')
+    expect(back).toHaveAttribute('href', expect.stringMatching(/meeting_key=1229/))
+    expect(back).toHaveAttribute('href', expect.stringMatching(/session_key=9472/))
+    expect(back.getAttribute('href')).toMatch(/^\//)
+
+    mockFetchRaceHub.mockResolvedValue(raceHub)
+    fireEvent.click(screen.getByTestId('rh-retry'))
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+  })
+
+  it('exposes a Back to Weekend link that carries meeting and session context', async () => {
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+    const back = screen.getByRole('link', { name: 'Back to Weekend' })
+    expect(back).toHaveAttribute('data-testid', 'rh-back-weekend')
+    expect(back).toHaveAttribute('href', expect.stringMatching(/meeting_key=1229/))
+    expect(back).toHaveAttribute('href', expect.stringMatching(/session_key=9472/))
+  })
 })

frontend/src/test/RacePreviewPage.test.tsx

@@ -0,0 +1,277 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, waitFor } from '@testing-library/react'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { RouterProvider, createRouter, createRootRoute, createRoute } from '@tanstack/react-router'
+import { RacePreviewPage } from '../pages/RacePreviewPage'
+import type { ChampHubDriver, ChampionshipHub, EnrichedGrid, EnrichedResult, Meeting, Session, TrackOutline } from '../types'
+
+vi.mock('../api', () => ({
+  fetchSeasons: vi.fn(),
+  fetchMeetings: vi.fn(),
+  fetchSessions: vi.fn(),
+  fetchResults: vi.fn(),
+  fetchStartingGrid: vi.fn(),
+  fetchTrackOutline: vi.fn(),
+  fetchChampionshipHub: vi.fn(),
+}))
+
+import {
+  fetchSeasons,
+  fetchMeetings,
+  fetchSessions,
+  fetchResults,
+  fetchStartingGrid,
+  fetchTrackOutline,
+  fetchChampionshipHub,
+} from '../api'
+
+const mockFetchSeasons = vi.mocked(fetchSeasons)
+const mockFetchMeetings = vi.mocked(fetchMeetings)
+const mockFetchSessions = vi.mocked(fetchSessions)
+const mockFetchResults = vi.mocked(fetchResults)
+const mockFetchStartingGrid = vi.mocked(fetchStartingGrid)
+const mockFetchTrackOutline = vi.mocked(fetchTrackOutline)
+const mockFetchChampionshipHub = vi.mocked(fetchChampionshipHub)
+
+const upcomingMeeting: Meeting = {
+  meeting_key: 100,
+  meeting_name: 'Monaco',
+  meeting_official_name: 'Monaco GP',
+  location: 'Monaco',
+  country_name: 'Monaco',
+  country_code: 'MON',
+  country_flag: '',
+  circuit_key: 10,
+  circuit_short_name: 'Monaco',
+  date_start: '2099-05-22T00:00:00+00:00',
+  date_end: '2099-05-24T23:59:59+00:00',
+  year: 2099,
+}
+
+const priorMeeting: Meeting = {
+  ...upcomingMeeting,
+  meeting_key: 90,
+  year: 2098,
+  date_start: '2098-05-22T00:00:00+00:00',
+  date_end: '2098-05-24T23:59:59+00:00',
+}
+
+const sessions: Session[] = [
+  {
+    session_key: 1,
+    session_name: 'FP1',
+    session_type: 'Practice',
+    meeting_key: 100,
+    date_start: '2099-05-22T10:00:00+00:00',
+    date_end: '2099-05-22T11:00:00+00:00',
+    gmt_offset: '02:00:00',
+  },
+  {
+    session_key: 2,
+    session_name: 'Sprint',
+    session_type: 'Sprint',
+    meeting_key: 100,
+    date_start: '2099-05-23T10:00:00+00:00',
+    date_end: '2099-05-23T11:00:00+00:00',
+    gmt_offset: '02:00:00',
+  },
+  {
+    session_key: 3,
+    session_name: 'Race',
+    session_type: 'Race',
+    meeting_key: 100,
+    date_start: '2099-05-24T13:00:00+00:00',
+    date_end: '2099-05-24T15:00:00+00:00',
+    gmt_offset: '02:00:00',
+  },
+]
+
+const priorRaceSession: Session = {
+  session_key: 50,
+  session_name: 'Race',
+  session_type: 'Race',
+  meeting_key: 90,
+  date_start: '2098-05-24T13:00:00+00:00',
+  date_end: '2098-05-24T15:00:00+00:00',
+  gmt_offset: '02:00:00',
+}
+
+const hubDriver = (over: Partial<ChampHubDriver>): ChampHubDriver => ({
+  driver_number: 1,
+  name_acronym: 'VER',
+  full_name: 'Max Verstappen',
+  team_name: 'Red Bull',
+  team_colour: '3671c6',
+  points: 200,
+  position: 1,
+  wins: 5,
+  podiums: 8,
+  poles: 4,
+  form: [25],
+  cumulative: [200],
+  round_positions: [1],
+  teammate_wins: 9,
+  teammate_losses: 1,
+  ...over,
+})
+
+const hub: ChampionshipHub = {
+  season: 2099,
+  round: 5,
+  total_rounds: 24,
+  rounds_left: 19,
+  last_race: 'Monaco GP',
+  round_labels: ['R1'],
+  drivers: [
+    hubDriver({}),
+    hubDriver({ driver_number: 4, name_acronym: 'NOR', points: 160, position: 2 }),
+    hubDriver({ driver_number: 16, name_acronym: 'LEC', points: 120, position: 3 }),
+  ],
+  teams: [],
+}
+
+const results: EnrichedResult[] = [
+  {
+    driver_number: 1,
+    position: 1,
+    name_acronym: 'VER',
+    full_name: 'Max Verstappen',
+    team_name: 'Red Bull',
+    team_colour: '3671c6',
+    dnf: false,
+    dns: false,
+    dsq: false,
+    duration: 100,
+    gap_to_leader: 0,
+    number_of_laps: 78,
+    points: 25,
+    session_key: 50,
+    meeting_key: 90,
+  },
+]
+
+const grid: EnrichedGrid[] = [
+  {
+    driver_number: 4,
+    position: 1,
+    name_acronym: 'NOR',
+    full_name: 'Lando Norris',
+    team_name: 'McLaren',
+    team_colour: 'ff8000',
+    session_key: 50,
+    meeting_key: 90,
+    lap_duration: 70,
+  },
+]
+
+const outline: TrackOutline = {
+  circuit_key: 10,
+  points: [
+    { x: 0.1, y: 0.2 },
+    { x: 0.5, y: 0.5 },
+    { x: 0.9, y: 0.8 },
+  ],
+  bounds: { minX: 0, maxX: 1, minY: 0, maxY: 1 },
+}
+
+function renderPage() {
+  const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+  const rootRoute = createRootRoute({
+    component: () => (
+      <QueryClientProvider client={queryClient}>
+        <RacePreviewPage />
+      </QueryClientProvider>
+    ),
+  })
+  const indexRoute = createRoute({ getParentRoute: () => rootRoute, path: '/', component: RacePreviewPage })
+  const router = createRouter({ routeTree: rootRoute.addChildren([indexRoute]) })
+  return render(<RouterProvider router={router} />)
+}
+
+describe('RacePreviewPage', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockFetchSeasons.mockResolvedValue([2099])
+    mockFetchChampionshipHub.mockResolvedValue(hub)
+    mockFetchTrackOutline.mockResolvedValue(outline)
+    mockFetchResults.mockResolvedValue(results)
+    mockFetchStartingGrid.mockResolvedValue(grid)
+  })
+
+  it('renders upcoming race preview with sections', async () => {
+    mockFetchMeetings.mockImplementation(async (year: number) => {
+      if (year === 2099) return [upcomingMeeting]
+      if (year === 2098) return [priorMeeting]
+      return []
+    })
+    mockFetchSessions.mockImplementation(async (meetingKey: number) => {
+      if (meetingKey === 100) return sessions
+      if (meetingKey === 90) return [priorRaceSession]
+      return []
+    })
+
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('preview-page')).toBeInTheDocument()
+    })
+
+    await waitFor(() => {
+      expect(screen.getByTestId('preview-countdown')).toBeInTheDocument()
+    })
+
+    expect(screen.getByTestId('preview-header')).toHaveTextContent('Monaco')
+    expect(screen.getByTestId('preview-schedule')).toHaveTextContent('FP1')
+    expect(screen.getByTestId('preview-track-card')).toBeInTheDocument()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('preview-last-year-card')).toHaveTextContent('VER')
+    })
+
+    expect(screen.getByTestId('preview-title-fight-card')).toHaveTextContent('NOR')
+    expect(screen.getByTestId('preview-sprint-note')).toBeInTheDocument()
+  })
+
+  it('renders season-over state when no upcoming meeting', async () => {
+    mockFetchMeetings.mockResolvedValue([
+      {
+        ...upcomingMeeting,
+        date_start: '2020-05-22T00:00:00+00:00',
+        date_end: '2020-05-24T23:59:59+00:00',
+      },
+    ])
+
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('preview-season-over')).toBeInTheDocument()
+    })
+
+    expect(screen.getByText('Season complete')).toBeInTheDocument()
+    expect(screen.getByTestId('preview-title-fight-card')).toBeInTheDocument()
+    expect(screen.queryByTestId('preview-header')).not.toBeInTheDocument()
+  })
+
+  it('shows first-time circuit empty state', async () => {
+    const newCircuit: Meeting = {
+      ...upcomingMeeting,
+      meeting_key: 200,
+      circuit_key: 999,
+      meeting_name: 'New GP',
+    }
+
+    mockFetchMeetings.mockImplementation(async (year: number) => {
+      if (year === 2099) return [newCircuit]
+      if (year === 2098) return [priorMeeting]
+      return []
+    })
+    mockFetchSessions.mockResolvedValue(sessions)
+    mockFetchTrackOutline.mockResolvedValue(null)
+
+    renderPage()
+
+    await waitFor(() => {
+      expect(screen.getByTestId('preview-last-year-card')).toHaveTextContent('First time on the calendar')
+    })
+  })
+})

frontend/src/test/RaceStoryCanvas.test.tsx

@@ -0,0 +1,291 @@
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { fireEvent, render, screen, waitFor } from '@testing-library/react'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { RaceStoryCanvas } from '../components/RaceStoryCanvas'
+import type { Chapter, RaceHub, ReplayFramesResponse, TrackOutline } from '../types'
+
+vi.mock('../api', () => ({
+  fetchReplayFrames: vi.fn(),
+  fetchTrackOutline: vi.fn(),
+}))
+
+import { fetchReplayFrames, fetchTrackOutline } from '../api'
+
+const mockFetchReplayFrames = vi.mocked(fetchReplayFrames)
+const mockFetchTrackOutline = vi.mocked(fetchTrackOutline)
+
+const outline: TrackOutline = {
+  circuit_key: 1,
+  bounds: { minX: 0, maxX: 100, minY: 0, maxY: 100 },
+  points: [
+    { x: 0, y: 0 },
+    { x: 1, y: 0 },
+    { x: 1, y: 1 },
+  ],
+}
+
+const replay: ReplayFramesResponse = {
+  session_key: 99,
+  interval_ms: 5000,
+  start_time: '2025-05-25T13:00:00Z',
+  frames: [
+    { t: 0, cars: { '1': { x: 10, y: 20 } } },
+    { t: 5000, cars: { '1': { x: 50, y: 50 } } },
+  ],
+}
+
+const chapters: Chapter[] = [
+  {
+    kind: 'start',
+    title: 'Start',
+    headline: 'Lights out',
+    start_lap: 1,
+    end_lap: 1,
+    start_time: '2025-05-25T13:00:00Z',
+    end_time: '2025-05-25T13:01:00Z',
+    driver_numbers: [],
+  },
+  {
+    kind: 'safety_car',
+    title: 'Safety Car',
+    headline: 'Incident brings out the Safety Car',
+    start_lap: 2,
+    end_lap: 2,
+    start_time: '2025-05-25T13:05:00Z',
+    end_time: '2025-05-25T13:05:00Z',
+    driver_numbers: [],
+  },
+]
+
+const raceHub: RaceHub = {
+  source: 'local',
+  session_key: 99,
+  datasets: {
+    positions: { status: 'available', source: 'local', count: 2 },
+  },
+  meeting: {
+    meeting_key: 1,
+    meeting_name: 'Monaco Grand Prix',
+    meeting_official_name: 'FORMULA 1 GRAND PRIX DE MONACO 2025',
+    location: 'Monaco',
+    country_name: 'Monaco',
+    country_code: 'MON',
+    country_flag: '',
+    circuit_key: 1,
+    circuit_short_name: 'Monaco',
+    date_start: '2025-05-23T00:00:00Z',
+    date_end: '2025-05-25T00:00:00Z',
+    year: 2025,
+  },
+  session: {
+    session_key: 99,
+    session_name: 'Race',
+    session_type: 'Race',
+    circuit_key: 1,
+    meeting_key: 1,
+    date_start: '2025-05-25T13:00:00Z',
+    date_end: '2025-05-25T15:00:00Z',
+    gmt_offset: '02:00:00',
+  },
+  drivers: [],
+  results: [
+    {
+      driver_number: 1,
+      position: 1,
+      name_acronym: 'VER',
+      full_name: 'Max Verstappen',
+      team_name: 'Red Bull Racing',
+      team_colour: '3671C6',
+      dnf: false,
+      dns: false,
+      dsq: false,
+      duration: null,
+      gap_to_leader: null,
+      number_of_laps: 78,
+      points: 25,
+      session_key: 99,
+      meeting_key: 1,
+    },
+  ],
+  starting_grid: [
+    {
+      driver_number: 1,
+      position: 1,
+      name_acronym: 'VER',
+      full_name: 'Max Verstappen',
+      team_name: 'Red Bull Racing',
+      team_colour: '3671C6',
+      session_key: 99,
+      meeting_key: 1,
+      lap_duration: null,
+    },
+  ],
+  stints: [],
+  pit_stops: [],
+  positions: [
+    { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T13:00:00Z', position: 1 },
+    { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T13:05:00Z', position: 1 },
+  ],
+  race_control: [],
+  weather: [],
+  laps: [],
+  chapters,
+}
+
+function renderCanvas(overrides: Partial<RaceHub> = {}) {
+  const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+  return render(
+    <QueryClientProvider client={queryClient}>
+      <RaceStoryCanvas data={{ ...raceHub, ...overrides }} />
+    </QueryClientProvider>,
+  )
+}
+
+describe('RaceStoryCanvas replay map', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockFetchReplayFrames.mockResolvedValue(replay)
+    mockFetchTrackOutline.mockResolvedValue(outline)
+  })
+
+  it('probes replay frames on mount and opens the map when data is available', async () => {
+    renderCanvas()
+
+    await waitFor(() => expect(mockFetchReplayFrames).toHaveBeenCalledWith(99, 5000))
+    expect(mockFetchTrackOutline).toHaveBeenCalledWith(1, 2025)
+
+    const mapToggle = await screen.findByTestId('replay-map-toggle')
+    fireEvent.click(mapToggle)
+
+    expect(await screen.findByTestId('replay-track-map')).toBeInTheDocument()
+    expect(screen.getByTestId('replay-map-slot')).toBeInTheDocument()
+  })
+
+  it('hides the map toggle when replay frames are unavailable', async () => {
+    mockFetchReplayFrames.mockResolvedValue({ ...replay, frames: [] })
+    renderCanvas()
+
+    await waitFor(() => expect(mockFetchReplayFrames).toHaveBeenCalled())
+    await waitFor(() => expect(screen.queryByTestId('replay-map-toggle')).not.toBeInTheDocument())
+  })
+
+  it('uses full-width chart layout when the map is closed', async () => {
+    renderCanvas()
+
+    await waitFor(() => expect(mockFetchReplayFrames).toHaveBeenCalled())
+    const chart = screen.getByTestId('position-chart')
+    expect(chart).toHaveClass('rs-chart-container--full')
+    expect(screen.queryByTestId('replay-map-slot')).not.toBeInTheDocument()
+    expect(document.querySelector('.rs-replay-shell--split')).not.toBeInTheDocument()
+  })
+
+  it('uses lap timing rather than pre-race position samples for the chart scale', () => {
+    const laps = Array.from({ length: 20 }, (_, index) => ({
+      session_key: 99,
+      driver_number: 1,
+      meeting_key: 1,
+      lap_number: index + 1,
+      date_start: `2025-05-25T13:${String(index).padStart(2, '0')}:00Z`,
+      lap_duration: 60,
+      is_pit_out_lap: false,
+    }))
+
+    renderCanvas({
+      results: [{ ...raceHub.results[0], number_of_laps: 20 }],
+      laps,
+      positions: [
+        { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T12:00:00Z', position: 1 },
+        { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T13:20:00Z', position: 1 },
+      ],
+    })
+
+    // L10 is the end of the tenth 60s lap, exactly halfway through the race.
+    const lapTenLabel = screen.getByText('L10')
+    expect(lapTenLabel.previousElementSibling).toHaveAttribute('x1', '316')
+    // The pre-race position is retained as the starting grid at the left edge.
+    expect(document.querySelector('.rs-driver-line')).toHaveAttribute('points', '40,8 592,8 592,8')
+  })
+
+  it('maps cursor positions from rendered pixels to the SVG viewBox', () => {
+    renderCanvas()
+
+    const svg = document.querySelector('.rs-position-chart-svg')!
+    vi.spyOn(svg, 'getBoundingClientRect').mockReturnValue({
+      x: 0,
+      y: 0,
+      width: 1280,
+      height: 360,
+      top: 0,
+      right: 1280,
+      bottom: 360,
+      left: 0,
+      toJSON: () => ({}),
+    })
+
+    const pointerMove = new Event('pointermove', { bubbles: true })
+    Object.defineProperty(pointerMove, 'clientX', { value: 640 })
+    fireEvent(screen.getByTestId('position-chart-interaction'), pointerMove)
+
+    // 640px is the middle of a 1280px rendered chart, which is x=320 in its 640-unit viewBox.
+    expect(document.querySelector('.rs-playhead')).toHaveAttribute('x1', '320')
+  })
+
+  it('syncs active chapter highlight when a chapter card is clicked', async () => {
+    renderCanvas()
+
+    fireEvent.click(screen.getByTestId('chapter-card-1'))
+    await waitFor(() => expect(screen.getByTestId('chapter-card-1')).toHaveClass('active'))
+    expect(screen.getByTestId('chapter-card-0')).not.toHaveClass('active')
+  })
+
+  it('highlights out-of-window chapters after click (clamped scrub + selection)', async () => {
+    // Position samples start at 13:05; start chapter ends at 13:01 — outside the window.
+    renderCanvas({
+      positions: [
+        { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T13:05:00Z', position: 1 },
+        { session_key: 99, driver_number: 1, meeting_key: 1, date: '2025-05-25T13:10:00Z', position: 1 },
+      ],
+      chapters: [
+        {
+          kind: 'start',
+          title: 'Start',
+          headline: 'Lights out before samples',
+          start_lap: 1,
+          end_lap: 1,
+          start_time: '2025-05-25T13:00:00Z',
+          end_time: '2025-05-25T13:01:00Z',
+          driver_numbers: [],
+        },
+        {
+          kind: 'finish',
+          title: 'Finish',
+          headline: 'Flag after samples',
+          start_lap: 78,
+          end_lap: 78,
+          start_time: '2025-05-25T13:20:00Z',
+          end_time: '2025-05-25T13:21:00Z',
+          driver_numbers: [],
+        },
+      ],
+    })
+
+    fireEvent.click(screen.getByTestId('chapter-card-0'))
+    await waitFor(() => expect(screen.getByTestId('chapter-card-0')).toHaveClass('active'))
+    expect(screen.getByTestId('chapter-card-1')).not.toHaveClass('active')
+
+    fireEvent.click(screen.getByTestId('chapter-card-1'))
+    await waitFor(() => expect(screen.getByTestId('chapter-card-1')).toHaveClass('active'))
+    expect(screen.getByTestId('chapter-card-0')).not.toHaveClass('active')
+  })
+
+  it('renders the empty-state card when positions are unavailable', () => {
+    renderCanvas({
+      datasets: { positions: { status: 'missing', source: 'local', count: 0 } },
+      positions: [],
+      chapters: [],
+    })
+
+    expect(screen.getByTestId('race-story-no-positions')).toBeInTheDocument()
+    expect(screen.getByText('Lap-by-lap positions not available')).toBeInTheDocument()
+  })
+})

frontend/src/test/ReplayTrackMap.test.tsx

@@ -0,0 +1,57 @@
+import { describe, expect, it } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import { ReplayTrackMap } from '../components/ReplayTrackMap'
+import type { EnrichedResult, ReplayFramesResponse, TrackOutline } from '../types'
+
+const outline: TrackOutline = {
+  circuit_key: 1,
+  bounds: { minX: 0, maxX: 100, minY: 0, maxY: 100 },
+  points: [
+    { x: 0, y: 0 },
+    { x: 1, y: 0 },
+    { x: 1, y: 1 },
+  ],
+}
+
+const replay: ReplayFramesResponse = {
+  session_key: 99,
+  interval_ms: 5000,
+  start_time: '2025-05-25T13:00:00Z',
+  frames: [
+    { t: 0, cars: { '1': { x: 0, y: 0 } } },
+    { t: 5000, cars: { '1': { x: 50, y: 50 } } },
+  ],
+}
+
+const results: EnrichedResult[] = [
+  {
+    driver_number: 1,
+    position: 1,
+    name_acronym: 'VER',
+    full_name: 'Max Verstappen',
+    team_name: 'Red Bull Racing',
+    team_colour: '3671C6',
+    dnf: false,
+    dns: false,
+    dsq: false,
+    duration: null,
+    gap_to_leader: null,
+    number_of_laps: 78,
+    points: 25,
+    session_key: 99,
+    meeting_key: 1,
+  },
+]
+
+describe('ReplayTrackMap', () => {
+  it('renders an empty-state card when replay frames are missing', () => {
+    render(<ReplayTrackMap outline={outline} replay={{ ...replay, frames: [] }} tMs={0} drivers={[]} results={results} />)
+    expect(screen.getByTestId('replay-map-no-frames')).toBeInTheDocument()
+    expect(screen.getByText('Historical GPS unavailable')).toBeInTheDocument()
+  })
+
+  it('renders car labels from result metadata', () => {
+    render(<ReplayTrackMap outline={outline} replay={replay} tMs={2500} drivers={[]} results={results} />)
+    expect(screen.getByLabelText(/VER replay position/i)).toBeInTheDocument()
+  })
+})

frontend/src/test/RivalryCompare.test.tsx

@@ -0,0 +1,114 @@
+import { describe, it, expect } from 'vitest'
+import { render, screen, fireEvent } from '@testing-library/react'
+import { RivalryCompare } from '../components/RivalryCompare'
+import type { ChampHubDriver, ChampionshipHub } from '../types'
+
+function driver(over: Partial<ChampHubDriver>): ChampHubDriver {
+  return {
+    driver_number: 1,
+    name_acronym: 'VER',
+    full_name: 'Max Verstappen',
+    team_name: 'Red Bull',
+    team_colour: '3671c6',
+    points: 100,
+    position: 1,
+    wins: 2,
+    podiums: 3,
+    poles: 1,
+    form: [25, 18, 25],
+    cumulative: [25, 43, 68],
+    round_positions: [1, 2, 1],
+    teammate_wins: 3,
+    teammate_losses: 0,
+    ...over,
+  }
+}
+
+function makeHub(drivers: ChampHubDriver[]): ChampionshipHub {
+  return {
+    season: 2025,
+    round: 3,
+    total_rounds: 10,
+    rounds_left: 7,
+    last_race: 'Japan GP',
+    round_labels: ['R1', 'R2', 'R3'],
+    drivers,
+    teams: [],
+  }
+}
+
+const hub = makeHub([
+  driver({}),
+  driver({
+    driver_number: 4,
+    name_acronym: 'NOR',
+    full_name: 'Lando Norris',
+    team_name: 'McLaren',
+    team_colour: 'ff8000',
+    points: 90,
+    position: 2,
+    cumulative: [18, 43, 61],
+    round_positions: [2, 1, 2],
+  }),
+  driver({
+    driver_number: 16,
+    name_acronym: 'LEC',
+    full_name: 'Charles Leclerc',
+    team_name: 'Ferrari',
+    team_colour: 'e8002d',
+    points: 50,
+    position: 3,
+    cumulative: [15, 28, 40],
+    round_positions: [3, 0, 3],
+  }),
+])
+
+describe('RivalryCompare', () => {
+  it('defaults to the top two drivers and shows the H2H score', () => {
+    render(<RivalryCompare hub={hub} />)
+
+    expect(screen.getByTestId('champ-view-rivalry')).toBeInTheDocument()
+    expect(screen.getByTestId('rivalry-pick-a')).toHaveValue('1')
+    expect(screen.getByTestId('rivalry-pick-b')).toHaveValue('4')
+    // VER wins R1 and R3, NOR wins R2.
+    expect(screen.getByTestId('rivalry-h2h-num')).toHaveTextContent('2–1')
+    expect(screen.getByText('3 rounds counted', { exact: false })).toBeInTheDocument()
+    expect(screen.getByTestId('rivalry-points-race')).toBeInTheDocument()
+    expect(screen.getByTestId('rivalry-gap')).toBeInTheDocument()
+    // Last gap: 68 − 61 = +7 → VER ahead.
+    expect(screen.getByText('VER leads by 7 pts', { exact: false })).toBeInTheDocument()
+  })
+
+  it('recomputes when a different driver is picked and skips missing rounds', () => {
+    render(<RivalryCompare hub={hub} />)
+
+    fireEvent.change(screen.getByTestId('rivalry-pick-b'), { target: { value: '16' } })
+
+    // VER vs LEC: R2 skipped (LEC has no position), VER wins R1 and R3.
+    expect(screen.getByTestId('rivalry-h2h-num')).toHaveTextContent('2–0')
+    expect(screen.getByText('2 rounds counted · 1 skipped', { exact: false })).toBeInTheDocument()
+  })
+
+  it('shows an empty state with fewer than two drivers', () => {
+    render(<RivalryCompare hub={makeHub([driver({})])} />)
+    expect(screen.getByTestId('champ-view-rivalry')).toHaveTextContent('at least two drivers')
+  })
+
+  it('shows an empty message when no rounds are completed', () => {
+    const empty = makeHub([
+      driver({ cumulative: [], round_positions: [], form: [] }),
+      driver({
+        driver_number: 4,
+        name_acronym: 'NOR',
+        cumulative: [],
+        round_positions: [],
+        form: [],
+      }),
+    ])
+    empty.round = 0
+    empty.round_labels = []
+
+    render(<RivalryCompare hub={empty} />)
+    expect(screen.getByTestId('champ-view-rivalry')).toHaveTextContent('No completed rounds yet')
+  })
+})

frontend/src/test/TabBar.test.tsx

@@ -3,7 +3,7 @@ import { render, screen, fireEvent } from '@testing-library/react'
 import { TabBar } from '../components/TabBar'
 
 describe('TabBar', () => {
-  it('renders all Race Hub workspace tabs', () => {
+  it('renders all Race Hub workspace tabs grouped into a hierarchy', () => {
     render(<TabBar active="overview" onChange={() => {}} />)
     expect(screen.getByRole('tab', { name: 'Overview' })).toBeInTheDocument()
     expect(screen.getByRole('tab', { name: 'Race Story' })).toBeInTheDocument()
@@ -12,7 +12,11 @@ describe('TabBar', () => {
     expect(screen.getByRole('tab', { name: 'Lap Data' })).toBeInTheDocument()
     expect(screen.getByRole('tab', { name: 'Conditions' })).toBeInTheDocument()
     expect(screen.getByRole('tab', { name: 'Race Control' })).toBeInTheDocument()
-    expect(screen.getByRole('tab', { name: 'Data Status' })).toBeInTheDocument()
+    expect(screen.getByRole('tab', { name: 'Diagnostics' })).toBeInTheDocument()
+
+    expect(screen.getByTestId('rh-tabgroup-story')).toBeInTheDocument()
+    expect(screen.getByTestId('rh-tabgroup-analysis')).toBeInTheDocument()
+    expect(screen.getByTestId('rh-tabgroup-context')).toBeInTheDocument()
   })
 
   it('marks the active tab with aria-selected', () => {

frontend/src/test/TeammateH2H.test.tsx

@@ -0,0 +1,54 @@
+import { describe, expect, it } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import { TeammateH2H } from '../components/TeammateH2H'
+
+describe('TeammateH2H', () => {
+  it('renders score and TLAs', () => {
+    render(
+      <TeammateH2H
+        teamName="Red Bull"
+        teamColour="3671c6"
+        driverATla="VER"
+        driverBTla="PER"
+        winsA={9}
+        winsB={1}
+      />,
+    )
+    expect(screen.getByText('VER')).toBeInTheDocument()
+    expect(screen.getByText('PER')).toBeInTheDocument()
+    expect(screen.getByTestId('h2h-score')).toHaveTextContent('9–1')
+    expect(screen.getByText('Red Bull')).toBeInTheDocument()
+  })
+
+  it('sets proportional bar segment widths from wins', () => {
+    render(
+      <TeammateH2H
+        teamName="McLaren"
+        teamColour="ff8000"
+        driverATla="NOR"
+        driverBTla="PIA"
+        winsA={6}
+        winsB={4}
+      />,
+    )
+    const barA = screen.getByTestId('h2h-bar-a')
+    const barB = screen.getByTestId('h2h-bar-b')
+    expect(barA).toHaveStyle({ width: '60%' })
+    expect(barB).toHaveStyle({ width: '40%' })
+  })
+
+  it('shows extra driver note when provided', () => {
+    render(
+      <TeammateH2H
+        teamName="Red Bull"
+        teamColour="3671c6"
+        driverATla="VER"
+        driverBTla="PER"
+        winsA={5}
+        winsB={3}
+        extraNote="+1"
+      />,
+    )
+    expect(screen.getByText('+1')).toBeInTheDocument()
+  })
+})

frontend/src/test/WeekendPage.test.tsx

@@ -0,0 +1,357 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
+import { render, screen, waitFor } from '@testing-library/react'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import {
+  Outlet,
+  RouterProvider,
+  createRouter,
+  createRootRoute,
+  createRoute,
+  createMemoryHistory,
+} from '@tanstack/react-router'
+import { WeekendPage } from '../pages/WeekendPage'
+import type {
+  ChampionshipHub,
+  ContextAvailability,
+  ContextSession,
+  Meeting,
+  RaceHub,
+  Session,
+  TemporalState,
+  WeekendContext,
+} from '../types'
+import { parseWeekendSearch } from '../lib/routeSearch'
+
+vi.mock('../api', () => ({
+  fetchWeekendContext: vi.fn(),
+  fetchChampionshipHub: vi.fn(),
+  fetchNews: vi.fn(),
+  fetchRaceHub: vi.fn(),
+  fetchWeekend: vi.fn(),
+  // Consumed transitively by RacePreviewPage (folded into PreSessionView):
+  fetchSeasons: vi.fn(),
+  fetchMeetings: vi.fn(),
+  fetchSessions: vi.fn(),
+  fetchResults: vi.fn(),
+  fetchStartingGrid: vi.fn(),
+  fetchTrackOutline: vi.fn(),
+}))
+
+import {
+  fetchWeekendContext,
+  fetchChampionshipHub,
+  fetchNews,
+  fetchRaceHub,
+  fetchWeekend,
+  fetchSeasons,
+  fetchMeetings,
+  fetchSessions,
+  fetchResults,
+  fetchStartingGrid,
+  fetchTrackOutline,
+} from '../api'
+
+const mockContext = vi.mocked(fetchWeekendContext)
+const mockHub = vi.mocked(fetchChampionshipHub)
+const mockNews = vi.mocked(fetchNews)
+const mockRaceHub = vi.mocked(fetchRaceHub)
+const mockWeekend = vi.mocked(fetchWeekend)
+const mockSeasons = vi.mocked(fetchSeasons)
+const mockMeetings = vi.mocked(fetchMeetings)
+const mockSessions = vi.mocked(fetchSessions)
+const mockResults = vi.mocked(fetchResults)
+const mockGrid = vi.mocked(fetchStartingGrid)
+const mockTrack = vi.mocked(fetchTrackOutline)
+
+function availability(overrides: Partial<ContextAvailability> = {}): ContextAvailability {
+  return {
+    schedule: 'available',
+    live_transport: 'unknown',
+    live_session: 'inactive',
+    archive: 'unavailable',
+    local_analysis: 'complete',
+    freshness: 'fresh',
+    limitations: [],
+    ...overrides,
+  }
+}
+
+function meeting(overrides: Partial<Meeting> = {}): Meeting {
+  return {
+    meeting_key: 1,
+    meeting_name: 'British Grand Prix',
+    meeting_official_name: 'FORMULA 1 BRITISH GRAND PRIX',
+    location: 'Silverstone',
+    country_name: 'United Kingdom',
+    country_code: 'GBR',
+    country_flag: '',
+    circuit_key: 2,
+    circuit_short_name: 'Silverstone',
+    date_start: '2026-07-03T09:00:00Z',
+    date_end: '2026-07-05T16:00:00Z',
+    year: 2026,
+    ...overrides,
+  }
+}
+
+function session(overrides: Partial<Session> = {}): Session {
+  return {
+    session_key: 11,
+    session_name: 'Race',
+    session_type: 'Race',
+    meeting_key: 1,
+    date_start: '2026-07-05T14:00:00Z',
+    date_end: '2026-07-05T16:00:00Z',
+    gmt_offset: '',
+    ...overrides,
+  }
+}
+
+function ctxSession(overrides: Partial<ContextSession> = {}): ContextSession {
+  return {
+    session: session(),
+    meeting: meeting(),
+    availability: availability(),
+    ...overrides,
+  }
+}
+
+function context(overrides: Partial<WeekendContext> = {}): WeekendContext {
+  return {
+    season: 2026,
+    temporal_state: 'between_weekends',
+    championship_round: 5,
+    total_championship_rounds: 24,
+    ...overrides,
+  }
+}
+
+const hub: ChampionshipHub = {
+  season: 2026,
+  round: 5,
+  total_rounds: 24,
+  rounds_left: 19,
+  last_race: 'British GP',
+  round_labels: [],
+  drivers: [
+    { driver_number: 1, name_acronym: 'VER', full_name: 'Max', team_name: 'RB', team_colour: '3671c6', points: 120, position: 1, wins: 4, podiums: 5, poles: 3, form: [], cumulative: [95, 120], teammate_wins: 0, teammate_losses: 0, round_positions: [] },
+  ],
+  teams: [],
+}
+
+const raceHub = {
+  session_key: 11,
+  results: [
+    { driver_number: 1, position: 1, name_acronym: 'VER', full_name: 'Max', team_name: 'RB', team_colour: '3671c6', dnf: false, dns: false, dsq: false, duration: 5400, gap_to_leader: null },
+  ],
+} as unknown as RaceHub
+
+function renderAt(path: string) {
+  const queryClient = new QueryClient({ defaultOptions: { queries: { retry: false } } })
+
+  const rootRoute = createRootRoute({
+    component: () => (
+      <QueryClientProvider client={queryClient}>
+        <Outlet />
+      </QueryClientProvider>
+    ),
+  })
+  const homeRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/',
+    validateSearch: (s: Record<string, unknown>) => parseWeekendSearch(s),
+    component: function HomeRoute() {
+      const { meeting_key, session_key } = homeRoute.useSearch()
+      return <WeekendPage focusMeetingKey={meeting_key} focusSessionKey={session_key} />
+    },
+  })
+  const previewRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/preview',
+    component: () => <WeekendPage preview />,
+  })
+  const raceHubRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/race-hub',
+    validateSearch: (s: Record<string, unknown>) => {
+      const sk = Number(s.session_key)
+      return Number.isFinite(sk) && sk > 0 ? { session_key: sk } : {}
+    },
+    component: () => <div data-testid="race-hub-stub" />,
+  })
+  const stub = (p: string, id: string) =>
+    createRoute({ getParentRoute: () => rootRoute, path: p, component: () => <div data-testid={id} /> })
+
+  const router = createRouter({
+    routeTree: rootRoute.addChildren([
+      homeRoute,
+      previewRoute,
+      raceHubRoute,
+      stub('/live', 'live-stub'),
+      stub('/explore', 'explore-stub'),
+      stub('/championship', 'championship-stub'),
+      stub('/briefing', 'briefing-stub'),
+    ]),
+    history: createMemoryHistory({ initialEntries: [path] }),
+  })
+  return render(<RouterProvider router={router} />)
+}
+
+describe('WeekendPage canonical contract rendering', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    vi.setSystemTime(new Date('2026-07-08T12:00:00Z'))
+    mockHub.mockResolvedValue(hub)
+    mockNews.mockResolvedValue([])
+    mockRaceHub.mockResolvedValue(raceHub)
+    mockWeekend.mockResolvedValue({
+      source: 'local',
+      meeting_key: 1,
+      meeting: meeting(),
+      sessions: [
+        {
+          session: session({ session_key: 11, session_name: 'Race' }),
+          source: 'local',
+          datasets: {},
+        },
+      ],
+      default_session_key: 11,
+    })
+    mockSeasons.mockResolvedValue([2026])
+    mockMeetings.mockResolvedValue([meeting()])
+    mockSessions.mockResolvedValue([session()])
+    mockResults.mockResolvedValue([])
+    mockGrid.mockResolvedValue([])
+    mockTrack.mockResolvedValue(null)
+  })
+
+  afterEach(() => {
+    vi.useRealTimers()
+  })
+
+  it('shows the loading surface before the canonical context resolves', async () => {
+    mockContext.mockReturnValue(new Promise(() => {}))
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-loading')).toBeInTheDocument())
+  })
+
+  it('shows an explicit error surface when the canonical endpoint fails', async () => {
+    mockContext.mockRejectedValue(new Error('API 500: boom'))
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-error')).toBeInTheDocument())
+    expect(screen.getByTestId('weekend-error')).toHaveTextContent('boom')
+  })
+
+  const stateCases: Array<[TemporalState, string]> = [
+    ['between_weekends', 'weekend-between-races'],
+    ['post_weekend', 'weekend-between-races'],
+    ['season_complete', 'weekend-between-races'],
+    ['pre_session', 'weekend-pre-session'],
+    ['between_sessions', 'weekend-between-sessions'],
+    ['session_settling', 'weekend-between-sessions'],
+    ['session_live', 'weekend-live'],
+  ]
+
+  it.each(stateCases)('renders a designed surface for canonical temporal_state %s', async (temporal, testid) => {
+    mockContext.mockResolvedValue(
+      context({
+        temporal_state: temporal,
+        previous_completed_session: ctxSession({ session: session({ session_key: 11, session_name: 'Race' }) }),
+        default_analysis_session: ctxSession({ session: session({ session_key: 11 }) }),
+        next_meeting: meeting({ meeting_key: 2, meeting_name: 'Hungarian Grand Prix', date_start: '2026-07-24T09:00:00Z' }),
+        next_session: ctxSession({ session: session({ session_key: 21, session_name: 'Practice 1', date_start: '2026-07-24T09:00:00Z' }) }),
+        active_session: temporal === 'session_live'
+          ? ctxSession({ session: session({ session_key: 12, session_name: 'Race' }), availability: availability({ live_session: 'active' }) })
+          : undefined,
+        focus_meeting: meeting(),
+      }),
+    )
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-temporal-state', temporal))
+    expect(screen.getByTestId(testid)).toBeInTheDocument()
+  })
+
+  it('renders the limited surface for no_season and never falls through to it for a valid payload', async () => {
+    mockContext.mockResolvedValue(context({ temporal_state: 'no_season', championship_round: 0, total_championship_rounds: 0 }))
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-limited')).toBeInTheDocument())
+  })
+
+  it('between-races pairs the completed analysis CTA with the next-event countdown and championship impact', async () => {
+    mockContext.mockResolvedValue(
+      context({
+        previous_completed_session: ctxSession({ session: session({ session_key: 11, session_name: 'Race' }) }),
+        default_analysis_session: ctxSession({ session: session({ session_key: 11 }) }),
+        next_meeting: meeting({ meeting_key: 2, meeting_name: 'Hungarian Grand Prix', date_start: '2026-07-24T09:00:00Z' }),
+        next_session: ctxSession({ session: session({ session_key: 21, session_name: 'Practice 1', date_start: '2026-07-24T09:00:00Z' }) }),
+      }),
+    )
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('wk-last-event')).toBeInTheDocument())
+    expect(screen.getByTestId('wk-next-event')).toBeInTheDocument()
+    const story = screen.getByTestId('wk-explore-race-story')
+    expect(story).toHaveAttribute('href', expect.stringContaining('session_key=11'))
+    expect(screen.getByTestId('wk-prepare')).toHaveAttribute('href', '/preview')
+    await waitFor(() => expect(screen.getByTestId('wk-champ-impact')).toBeInTheDocument())
+    expect(screen.getByTestId('wk-season-nav')).toHaveTextContent('Round 5 of 24')
+  })
+
+  it('does not fan out to season/meeting/OpenF1/live queries when the canonical context succeeds', async () => {
+    mockContext.mockResolvedValue(context({ temporal_state: 'between_weekends' }))
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-between-races')).toBeInTheDocument())
+    // Only supplementary championship + news reads are allowed; no season /
+    // meetings / sessions / live fan-out from the Weekend home hook.
+    expect(mockSeasons).not.toHaveBeenCalled()
+    expect(mockSessions).not.toHaveBeenCalled()
+    // fetchMeetings may still be reached only through the folded preview surface,
+    // which is not mounted in the between-races state.
+    expect(mockMeetings).not.toHaveBeenCalled()
+  })
+
+  it('supplementary reads stay dormant while the canonical context is pending', async () => {
+    mockContext.mockReturnValue(new Promise(() => {}))
+    renderAt('/')
+    await waitFor(() => expect(screen.getByTestId('weekend-loading')).toBeInTheDocument())
+    expect(mockHub).not.toHaveBeenCalled()
+    expect(mockNews).not.toHaveBeenCalled()
+  })
+
+  it('the /preview alias renders the preparation surface instead of looping back', async () => {
+    mockContext.mockResolvedValue(
+      context({
+        temporal_state: 'between_weekends',
+        next_meeting: meeting({ meeting_key: 2, meeting_name: 'Hungarian Grand Prix', date_start: '2026-07-24T09:00:00Z' }),
+        next_session: ctxSession({ session: session({ session_key: 21, session_name: 'Practice 1', date_start: '2026-07-24T09:00:00Z' }) }),
+      }),
+    )
+    renderAt('/preview')
+    await waitFor(() => expect(screen.getByTestId('weekend-pre-session')).toBeInTheDocument())
+    expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-preview', 'true')
+    // The between-races surface must NOT be what /preview renders.
+    expect(screen.queryByTestId('weekend-between-races')).not.toBeInTheDocument()
+  })
+
+  it('restores Race Hub meeting/session focus from the Weekend URL search contract', async () => {
+    mockContext.mockResolvedValue(
+      context({
+        temporal_state: 'season_complete',
+        previous_completed_session: ctxSession({ session: session({ session_key: 11, session_name: 'Race' }) }),
+        default_analysis_session: ctxSession({ session: session({ session_key: 11 }) }),
+      }),
+    )
+    renderAt('/?meeting_key=1&session_key=11')
+    await waitFor(() => expect(screen.getByTestId('wk-focus-context')).toBeInTheDocument())
+    expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-meeting-key', '1')
+    expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-session-key', '11')
+    await waitFor(() =>
+      expect(screen.getByTestId('wk-focus-meeting')).toHaveTextContent('British Grand Prix'),
+    )
+    await waitFor(() =>
+      expect(screen.getByTestId('wk-focus-session')).toHaveTextContent('Race'),
+    )
+    const continueAnalysis = screen.getByRole('link', { name: /Continue analysis/i })
+    expect(continueAnalysis).toHaveAttribute('href', expect.stringContaining('session_key=11'))
+    expect(mockWeekend).toHaveBeenCalledWith(1)
+  })
+})

frontend/src/test/chapters.test.ts

@@ -0,0 +1,124 @@
+import { describe, expect, it } from 'vitest'
+import {
+  activeChapterIndex,
+  chapterBandFill,
+  chapterKindLabel,
+  chapterLapRange,
+  chapterStartScrub,
+  chapterTourDurations,
+  deCollideYPositions,
+  decimatedPositionLabels,
+} from '../lib/chapters'
+import type { Chapter } from '../types'
+
+const sampleChapters: Chapter[] = [
+  {
+    kind: 'start',
+    title: 'Start',
+    headline: 'Lights out — the field charges into Turn 1',
+    start_lap: 1,
+    end_lap: 1,
+    start_time: '2025-05-25T13:00:00Z',
+    end_time: '2025-05-25T13:01:00Z',
+    driver_numbers: [],
+  },
+  {
+    kind: 'safety_car',
+    title: 'Safety Car (L12-L15)',
+    headline: 'Sainz incident brings out the Safety Car — leaders dive for the pits',
+    start_lap: 12,
+    end_lap: 15,
+    start_time: '2025-05-25T13:12:00Z',
+    end_time: '2025-05-25T13:15:00Z',
+    driver_numbers: [55],
+  },
+]
+
+describe('chapters lib', () => {
+  it('labels chapter kinds', () => {
+    expect(chapterKindLabel('safety_car')).toBe('SC')
+    expect(chapterKindLabel('finish')).toBe('FIN')
+  })
+
+  it('formats lap ranges', () => {
+    expect(chapterLapRange(sampleChapters[0])).toBe('L1')
+    expect(chapterLapRange(sampleChapters[1])).toBe('L12–L15')
+  })
+
+  it('maps chapter start time to scrub position', () => {
+    const tMin = new Date('2025-05-25T13:00:00Z').getTime()
+    const tMax = new Date('2025-05-25T13:20:00Z').getTime()
+    const scrub = chapterStartScrub(sampleChapters[1], tMin, tMax - tMin)
+    expect(scrub).toBeCloseTo(0.6, 2)
+  })
+
+  it('finds active chapter from scrub time', () => {
+    const tMin = new Date('2025-05-25T13:00:00Z').getTime()
+    const tMax = new Date('2025-05-25T13:20:00Z').getTime()
+    const tRange = tMax - tMin
+    const scrub = (new Date('2025-05-25T13:13:00Z').getTime() - tMin) / tRange
+    expect(activeChapterIndex(sampleChapters, scrub, tMin, tRange)).toBe(1)
+  })
+
+  it('activates chapters whose timestamps clamp outside the position window', () => {
+    // Position samples only cover 13:05–13:10; chapters sit before/after that window.
+    const tMin = new Date('2025-05-25T13:05:00Z').getTime()
+    const tMax = new Date('2025-05-25T13:10:00Z').getTime()
+    const tRange = tMax - tMin
+    const outOfWindow: Chapter[] = [
+      {
+        kind: 'start',
+        title: 'Start',
+        headline: 'Lights out',
+        start_lap: 1,
+        end_lap: 1,
+        start_time: '2025-05-25T13:00:00Z',
+        end_time: '2025-05-25T13:01:00Z',
+        driver_numbers: [],
+      },
+      {
+        kind: 'finish',
+        title: 'Finish',
+        headline: 'Chequered flag',
+        start_lap: 78,
+        end_lap: 78,
+        start_time: '2025-05-25T13:20:00Z',
+        end_time: '2025-05-25T13:21:00Z',
+        driver_numbers: [],
+      },
+    ]
+
+    expect(chapterStartScrub(outOfWindow[0], tMin, tRange)).toBe(0)
+    expect(chapterStartScrub(outOfWindow[1], tMin, tRange)).toBe(1)
+    expect(activeChapterIndex(outOfWindow, 0, tMin, tRange)).toBe(0)
+    expect(activeChapterIndex(outOfWindow, 1, tMin, tRange)).toBe(1)
+    expect(activeChapterIndex(outOfWindow, 0.5, tMin, tRange)).toBeNull()
+  })
+
+  it('splits 90s evenly across chapters', () => {
+    expect(chapterTourDurations(sampleChapters)).toEqual([45_000, 45_000])
+  })
+
+  it('decimates position axis labels', () => {
+    expect(decimatedPositionLabels(22)).toEqual([1, 5, 10, 15, 20, 22])
+  })
+
+  it('returns chapter band fills by kind', () => {
+    expect(chapterBandFill('safety_car')).toContain('rgba')
+    expect(chapterBandFill('virtual_safety_car')).toContain('rgba')
+  })
+
+  it('de-collides overlapping label y positions', () => {
+    const adjusted = deCollideYPositions(
+      [
+        { key: 'a', y: 10 },
+        { key: 'b', y: 12 },
+        { key: 'c', y: 30 },
+      ],
+      12,
+    )
+    expect(adjusted.get('a')).toBe(10)
+    expect(adjusted.get('b')).toBe(22)
+    expect(adjusted.get('c')).toBe(34)
+  })
+})

frontend/src/test/digest.test.ts

@@ -0,0 +1,266 @@
+import { describe, it, expect } from 'vitest'
+import {
+  activeDigestWindow,
+  filterByTag,
+  groupByWindow,
+  gpWindows,
+  itemsForWindow,
+  sinceLastLabel,
+  sortWindowBucketsNewestFirst,
+  tagItems,
+  topTags,
+  windowForDate,
+} from '../lib/digest'
+import type { ChampHubDriver, ChampHubTeam, Meeting, NewsItem } from '../types'
+
+const meeting = (overrides: Partial<Meeting> = {}): Meeting => ({
+  meeting_key: 1,
+  meeting_name: 'Bahrain',
+  meeting_official_name: 'Bahrain GP',
+  location: 'Sakhir',
+  country_name: 'Bahrain',
+  country_code: 'BRN',
+  country_flag: '',
+  circuit_short_name: 'Sakhir',
+  date_start: '2025-03-14T00:00:00+00:00',
+  date_end: '2025-03-16T23:59:59+00:00',
+  year: 2025,
+  ...overrides,
+})
+
+const news = (overrides: Partial<NewsItem> = {}): NewsItem => ({
+  source: 'autosport-f1',
+  title: 'Headline',
+  url: `https://example.com/${Math.random()}`,
+  fetched_at: '2025-04-01T12:00:00Z',
+  ...overrides,
+})
+
+const driver = (over: Partial<ChampHubDriver>): ChampHubDriver => ({
+  driver_number: 1,
+  name_acronym: 'VER',
+  full_name: 'Max Verstappen',
+  team_name: 'Red Bull',
+  team_colour: '3671c6',
+  points: 100,
+  position: 1,
+  wins: 3,
+  podiums: 5,
+  poles: 2,
+  form: [25, 18, 25],
+  cumulative: [25, 43, 68, 100],
+  teammate_wins: 4,
+  teammate_losses: 1,
+  round_positions: [],
+  ...over,
+})
+
+const team = (over: Partial<ChampHubTeam>): ChampHubTeam => ({
+  team_name: 'Red Bull',
+  team_colour: '3671c6',
+  points: 150,
+  position: 1,
+  wins: 4,
+  ...over,
+})
+
+describe('gpWindows', () => {
+  const bahrain = meeting({ meeting_key: 1, meeting_name: 'Bahrain' })
+  const monaco = meeting({
+    meeting_key: 2,
+    meeting_name: 'Monaco',
+    date_start: '2025-05-23T00:00:00+00:00',
+    date_end: '2025-05-25T23:59:59+00:00',
+  })
+  const canada = meeting({
+    meeting_key: 3,
+    meeting_name: 'Canada',
+    date_start: '2025-06-13T00:00:00+00:00',
+    date_end: '2025-06-15T23:59:59+00:00',
+  })
+
+  it('derives inter-race windows mid-season', () => {
+    const now = new Date('2025-04-10T12:00:00Z')
+    const windows = gpWindows([bahrain, monaco, canada], now)
+
+    expect(windows).toHaveLength(3)
+    expect(windows[0].start).toBeNull()
+    expect(windows[0].end?.toISOString()).toBe(new Date('2025-05-23T00:00:00+00:00').toISOString())
+    expect(windows[1].start?.toISOString()).toBe(new Date('2025-03-16T23:59:59+00:00').toISOString())
+    expect(windows[1].end?.toISOString()).toBe(new Date('2025-06-13T00:00:00+00:00').toISOString())
+    expect(windows[2].start?.toISOString()).toBe(new Date('2025-05-25T23:59:59+00:00').toISOString())
+    expect(windows[2].end).toBeNull()
+  })
+
+  it('handles before the first race of the season', () => {
+    const now = new Date('2025-01-01T00:00:00Z')
+    const windows = gpWindows([bahrain, monaco], now)
+    expect(windows[0].start).toBeNull()
+    expect(activeDigestWindow(windows, [bahrain, monaco], now)?.meeting_name).toBe('Bahrain')
+    expect(sinceLastLabel([bahrain, monaco], now)).toBe('Before Bahrain')
+  })
+
+  it('handles after the final race of the season', () => {
+    const now = new Date('2025-12-01T00:00:00Z')
+    const windows = gpWindows([bahrain, monaco], now)
+    expect(activeDigestWindow(windows, [bahrain, monaco], now)?.meeting_name).toBe('Monaco')
+    expect(sinceLastLabel([bahrain, monaco], now)).toBe('Monaco')
+    expect(windows[1].end).toBeNull()
+  })
+})
+
+describe('groupByWindow', () => {
+  const bahrain = meeting({ meeting_key: 1 })
+  const monaco = meeting({
+    meeting_key: 2,
+    date_start: '2025-05-23T00:00:00+00:00',
+    date_end: '2025-05-25T23:59:59+00:00',
+  })
+  const windows = gpWindows([bahrain, monaco], new Date('2025-04-10T12:00:00Z'))
+
+  it('buckets dated items into the matching GP window', () => {
+    const items = [
+      news({ url: 'https://a', published_at: '2025-03-10T10:00:00Z', title: 'Pre-Bahrain' }),
+      news({ url: 'https://b', published_at: '2025-04-05T10:00:00Z', title: 'Between races' }),
+      news({ url: 'https://c', published_at: '2025-05-24T10:00:00Z', title: 'Monaco weekend' }),
+    ]
+
+    const grouped = groupByWindow(items, windows)
+    const bahrainItems = grouped.windows.find((entry) => entry.window.meeting_key === 1)?.items ?? []
+    const monacoItems = grouped.windows.find((entry) => entry.window.meeting_key === 2)?.items ?? []
+
+    expect(bahrainItems).toHaveLength(1)
+    expect(bahrainItems[0].title).toBe('Pre-Bahrain')
+    expect(monacoItems).toHaveLength(2)
+    expect(monacoItems.map((item) => item.title)).toEqual(['Between races', 'Monaco weekend'])
+  })
+
+  it('puts undated items in the recent bucket', () => {
+    const items = [
+      news({ url: 'https://u', title: 'Undated story' }),
+      news({ url: 'https://d', published_at: '2025-04-05T10:00:00Z' }),
+    ]
+    const grouped = groupByWindow(items, windows)
+    expect(grouped.recent).toHaveLength(1)
+    expect(grouped.recent[0].url).toBe('https://u')
+  })
+
+  it('sorts window buckets newest first for display', () => {
+    const items = [
+      news({ published_at: '2025-03-10T10:00:00Z' }),
+      news({ published_at: '2025-05-24T10:00:00Z' }),
+    ]
+    const grouped = groupByWindow(items, windows)
+    const sorted = sortWindowBucketsNewestFirst(grouped.windows)
+    expect(sorted[0].window.meeting_key).toBe(2)
+    expect(sorted[1].window.meeting_key).toBe(1)
+  })
+})
+
+describe('tagItems', () => {
+  const drivers = [
+    driver({ name_acronym: 'VER', full_name: 'Max Verstappen', team_name: 'Red Bull' }),
+    driver({
+      driver_number: 4,
+      name_acronym: 'NOR',
+      full_name: 'Lando Norris',
+      team_name: 'McLaren',
+      team_colour: 'ff8000',
+    }),
+  ]
+  const teams = [
+    team({ team_name: 'Red Bull' }),
+    team({ team_name: 'McLaren', team_colour: 'ff8000' }),
+  ]
+
+  it('tags drivers and teams case-insensitively', () => {
+    const [item] = tagItems(
+      [news({ title: 'ver leads mclaren in practice', summary: 'Norris close behind' })],
+      drivers,
+      teams,
+    )
+    const labels = item.tags.map((tag) => tag.label).sort()
+    expect(labels).toEqual(['McLaren', 'NOR', 'VER'])
+  })
+
+  it('returns no tags when nothing matches', () => {
+    const [item] = tagItems(
+      [news({ title: 'Generic paddock update' })],
+      drivers,
+      teams,
+    )
+    expect(item.tags).toEqual([])
+  })
+
+  it('prefers the longest overlapping match', () => {
+    const [item] = tagItems(
+      [news({ title: 'Max Verstappen extends championship lead' })],
+      drivers,
+      teams,
+    )
+    expect(item.tags).toHaveLength(1)
+    expect(item.tags[0].label).toBe('VER')
+  })
+
+  it('matches a driver last name inside prose', () => {
+    const [item] = tagItems(
+      [news({ title: 'Verstappen was untouchable in qualifying' })],
+      drivers,
+      teams,
+    )
+    expect(item.tags.some((tag) => tag.label === 'VER')).toBe(true)
+  })
+})
+
+describe('digest helpers', () => {
+  it('collects top tags by frequency', () => {
+    const tagged = tagItems(
+      [
+        news({ title: 'VER wins', url: 'https://a' }),
+        news({ title: 'VER dominates', url: 'https://b' }),
+        news({ title: 'Norris podium', url: 'https://c' }),
+      ],
+      [driver({}), driver({ driver_number: 4, name_acronym: 'NOR', full_name: 'Lando Norris', team_name: 'McLaren' })],
+      [team({}), team({ team_name: 'McLaren', team_colour: 'ff8000' })],
+    )
+    expect(topTags(tagged, 2).map((tag) => tag.label)).toEqual(['VER', 'NOR'])
+  })
+
+  it('filters items by tag key', () => {
+    const tagged = tagItems(
+      [
+        news({ title: 'VER wins', url: 'https://a' }),
+        news({ title: 'Neutral headline', url: 'https://b' }),
+      ],
+      [driver({})],
+      [team({})],
+    )
+    const filtered = filterByTag(tagged, 'driver:VER')
+    expect(filtered).toHaveLength(1)
+    expect(filtered[0].url).toBe('https://a')
+  })
+
+  it('selects items for the active digest window', () => {
+    const bahrain = meeting({ meeting_key: 1 })
+    const monaco = meeting({
+      meeting_key: 2,
+      date_start: '2025-05-23T00:00:00+00:00',
+      date_end: '2025-05-25T23:59:59+00:00',
+    })
+    const now = new Date('2025-04-10T12:00:00Z')
+    const windows = gpWindows([bahrain, monaco], now)
+    const active = activeDigestWindow(windows, [bahrain, monaco], now)
+    const tagged = tagItems(
+      [
+        news({ published_at: '2025-04-05T10:00:00Z', url: 'https://in' }),
+        news({ published_at: '2025-03-10T10:00:00Z', url: 'https://out' }),
+      ],
+      [],
+      [],
+    )
+    const inWindow = itemsForWindow(tagged, active)
+    expect(inWindow).toHaveLength(1)
+    expect(inWindow[0].url).toBe('https://in')
+    expect(windowForDate(windows, new Date('2025-04-05T10:00:00Z'))?.meeting_key).toBe(2)
+  })
+})

frontend/src/test/driverProfile.test.ts

@@ -0,0 +1,104 @@
+import { describe, it, expect } from 'vitest'
+import {
+  formatDelta,
+  formatPosition,
+  gridFinishDeltas,
+  shortGpLabel,
+} from '../lib/driverProfile'
+import type { DriverSummaryRound } from '../types'
+
+function round(over: Partial<DriverSummaryRound>): DriverSummaryRound {
+  return {
+    meeting_key: 1201,
+    meeting_name: 'Bahrain Grand Prix',
+    country_code: 'BHR',
+    country_name: 'Bahrain',
+    race_position: 1,
+    grid_position: 1,
+    quali_position: 1,
+    points: 25,
+    dnf: false,
+    dns: false,
+    dsq: false,
+    ...over,
+  }
+}
+
+describe('gridFinishDeltas', () => {
+  it('computes positive delta for places gained', () => {
+    const [d] = gridFinishDeltas([round({ grid_position: 5, race_position: 2, points: 18 })])
+    expect(d.grid).toBe(5)
+    expect(d.finish).toBe(2)
+    expect(d.delta).toBe(3)
+    expect(d.points).toBe(18)
+    expect(d.status).toBe('classified')
+    expect(d.round).toBe(1)
+  })
+
+  it('computes negative delta for places lost', () => {
+    const [d] = gridFinishDeltas([round({ grid_position: 1, race_position: 4 })])
+    expect(d.delta).toBe(-3)
+  })
+
+  it('returns null delta when the grid slot is unknown (position 0)', () => {
+    const [d] = gridFinishDeltas([round({ grid_position: 0, race_position: 6 })])
+    expect(d.grid).toBeNull()
+    expect(d.finish).toBe(6)
+    expect(d.delta).toBeNull()
+  })
+
+  it('flags DNS rounds and never computes a delta for them', () => {
+    const [d] = gridFinishDeltas([round({ dns: true, grid_position: 8, race_position: 0 })])
+    expect(d.status).toBe('dns')
+    expect(d.delta).toBeNull()
+  })
+
+  it('marks rounds the driver did not enter as absent', () => {
+    const [d] = gridFinishDeltas([round({ grid_position: 0, race_position: 0, points: 0 })])
+    expect(d.status).toBe('absent')
+    expect(d.grid).toBeNull()
+    expect(d.finish).toBeNull()
+    expect(d.delta).toBeNull()
+  })
+
+  it('still computes the delta for a classified DNF with known positions', () => {
+    const [d] = gridFinishDeltas([round({ dnf: true, grid_position: 3, race_position: 15 })])
+    expect(d.status).toBe('dnf')
+    expect(d.delta).toBe(-12)
+  })
+
+  it('numbers rounds sequentially and shortens labels', () => {
+    const ds = gridFinishDeltas([
+      round({}),
+      round({ meeting_name: 'Saudi Arabian Grand Prix', meeting_key: 1202 }),
+    ])
+    expect(ds.map((d) => d.round)).toEqual([1, 2])
+    expect(ds[1].label).toBe('Saudi Arabian')
+  })
+})
+
+describe('shortGpLabel', () => {
+  it('strips "Grand Prix" wherever it appears', () => {
+    expect(shortGpLabel('Bahrain Grand Prix')).toBe('Bahrain')
+    expect(shortGpLabel('Grand Prix of Monaco')).toBe('of Monaco')
+  })
+
+  it('falls back to the original name when stripping empties it', () => {
+    expect(shortGpLabel('Grand Prix')).toBe('Grand Prix')
+  })
+})
+
+describe('formatPosition / formatDelta', () => {
+  it('formats positions', () => {
+    expect(formatPosition(4)).toBe('P4')
+    expect(formatPosition(null)).toBe('—')
+    expect(formatPosition(0)).toBe('—')
+  })
+
+  it('formats deltas', () => {
+    expect(formatDelta(3)).toBe('+3')
+    expect(formatDelta(-2)).toBe('−2')
+    expect(formatDelta(0)).toBe('=')
+    expect(formatDelta(null)).toBe('—')
+  })
+})

frontend/src/test/h2h.test.ts

@@ -0,0 +1,133 @@
+import { describe, expect, it } from 'vitest'
+import { teammatePairs } from '../lib/h2h'
+import type { ChampHubDriver } from '../types'
+
+function driver(over: Partial<ChampHubDriver>): ChampHubDriver {
+  return {
+    driver_number: 1,
+    name_acronym: 'VER',
+    full_name: 'Max Verstappen',
+    team_name: 'Red Bull',
+    team_colour: '3671c6',
+    points: 200,
+    position: 1,
+    wins: 5,
+    podiums: 8,
+    poles: 4,
+    form: [],
+    cumulative: [],
+    teammate_wins: 9,
+    teammate_losses: 1,
+    round_positions: [],
+    ...over,
+  }
+}
+
+describe('teammatePairs', () => {
+  it('returns empty for no drivers', () => {
+    expect(teammatePairs([])).toEqual([])
+  })
+
+  it('skips teams with a single driver', () => {
+    const drivers = [
+      driver({ driver_number: 1, team_name: 'Red Bull' }),
+      driver({ driver_number: 44, name_acronym: 'HAM', team_name: 'Mercedes', points: 50 }),
+    ]
+    expect(teammatePairs(drivers)).toHaveLength(0)
+  })
+
+  it('pairs two-driver teams', () => {
+    const drivers = [
+      driver({ driver_number: 1, name_acronym: 'VER', points: 200, teammate_wins: 9, teammate_losses: 1 }),
+      driver({
+        driver_number: 11,
+        name_acronym: 'PER',
+        full_name: 'Sergio Perez',
+        points: 60,
+        teammate_wins: 1,
+        teammate_losses: 9,
+      }),
+    ]
+    const pairs = teammatePairs(drivers)
+    expect(pairs).toHaveLength(1)
+    expect(pairs[0].teamName).toBe('Red Bull')
+    expect(pairs[0].driverA.name_acronym).toBe('VER')
+    expect(pairs[0].driverB.name_acronym).toBe('PER')
+    expect(pairs[0].extraCount).toBe(0)
+    expect(pairs[0].closeness).toBe(8)
+  })
+
+  it('uses top two by points for teams with 3+ drivers', () => {
+    const drivers = [
+      driver({ driver_number: 1, name_acronym: 'VER', team_name: 'Red Bull', points: 200 }),
+      driver({
+        driver_number: 11,
+        name_acronym: 'PER',
+        team_name: 'Red Bull',
+        points: 60,
+        teammate_wins: 1,
+        teammate_losses: 9,
+      }),
+      driver({
+        driver_number: 99,
+        name_acronym: 'LAW',
+        full_name: 'Liam Lawson',
+        team_name: 'Red Bull',
+        points: 10,
+        teammate_wins: 0,
+        teammate_losses: 0,
+      }),
+    ]
+    const pairs = teammatePairs(drivers)
+    expect(pairs).toHaveLength(1)
+    expect(pairs[0].driverA.name_acronym).toBe('VER')
+    expect(pairs[0].driverB.name_acronym).toBe('PER')
+    expect(pairs[0].extraCount).toBe(1)
+  })
+
+  it('sorts by closest battle first', () => {
+    const drivers = [
+      driver({
+        driver_number: 1,
+        name_acronym: 'VER',
+        team_name: 'Red Bull',
+        points: 200,
+        teammate_wins: 10,
+        teammate_losses: 0,
+      }),
+      driver({
+        driver_number: 11,
+        name_acronym: 'PER',
+        team_name: 'Red Bull',
+        points: 60,
+        teammate_wins: 0,
+        teammate_losses: 10,
+      }),
+      driver({
+        driver_number: 4,
+        name_acronym: 'NOR',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        points: 160,
+        teammate_wins: 6,
+        teammate_losses: 5,
+      }),
+      driver({
+        driver_number: 81,
+        name_acronym: 'PIA',
+        full_name: 'Oscar Piastri',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        points: 140,
+        teammate_wins: 5,
+        teammate_losses: 6,
+      }),
+    ]
+    const pairs = teammatePairs(drivers)
+    expect(pairs).toHaveLength(2)
+    expect(pairs[0].teamName).toBe('McLaren')
+    expect(pairs[0].closeness).toBe(1)
+    expect(pairs[1].teamName).toBe('Red Bull')
+    expect(pairs[1].closeness).toBe(10)
+  })
+})

frontend/src/test/preview.test.ts

@@ -0,0 +1,227 @@
+import { describe, it, expect } from 'vitest'
+import type { ChampHubDriver, ChampionshipHub, EnrichedGrid, EnrichedResult, Meeting, Session } from '../types'
+import {
+  buildTitleFightContext,
+  countdownTargetSession,
+  extractPodium,
+  extractPole,
+  findPriorYearMeetingByCircuit,
+  findRaceSession,
+  formatPointsGap,
+  isSprintWeekend,
+  pickPreviewMeeting,
+  RACE_WIN_POINTS,
+  SPRINT_WEEKEND_MAX_POINTS,
+} from '../lib/preview'
+
+const meeting = (overrides: Partial<Meeting> = {}): Meeting => ({
+  meeting_key: 1,
+  meeting_name: 'Monaco',
+  meeting_official_name: 'Monaco GP',
+  location: 'Monaco',
+  country_name: 'Monaco',
+  country_code: 'MON',
+  country_flag: '',
+  circuit_key: 10,
+  circuit_short_name: 'Monaco',
+  date_start: '2026-05-22T00:00:00+00:00',
+  date_end: '2026-05-24T23:59:59+00:00',
+  year: 2026,
+  ...overrides,
+})
+
+const session = (overrides: Partial<Session> = {}): Session => ({
+  session_key: 100,
+  session_name: 'Race',
+  session_type: 'Race',
+  meeting_key: 1,
+  date_start: '2026-05-24T13:00:00+00:00',
+  date_end: '2026-05-24T15:00:00+00:00',
+  gmt_offset: '02:00:00',
+  ...overrides,
+})
+
+const hubDriver = (over: Partial<ChampHubDriver>): ChampHubDriver => ({
+  driver_number: 1,
+  name_acronym: 'VER',
+  full_name: 'Max Verstappen',
+  team_name: 'Red Bull',
+  team_colour: '3671c6',
+  points: 200,
+  position: 1,
+  wins: 5,
+  podiums: 8,
+  poles: 4,
+  form: [25],
+  cumulative: [200],
+  round_positions: [1],
+  teammate_wins: 9,
+  teammate_losses: 1,
+  ...over,
+})
+
+describe('preview lib', () => {
+  it('picks the next upcoming meeting', () => {
+    const now = new Date('2026-01-01T00:00:00Z')
+    const meetings = [
+      meeting({ meeting_key: 1, date_start: '2026-05-22T00:00:00+00:00' }),
+      meeting({ meeting_key: 2, meeting_name: 'Spain', date_start: '2026-06-12T00:00:00+00:00' }),
+    ]
+    expect(pickPreviewMeeting(meetings, now)?.meeting_key).toBe(1)
+  })
+
+  it('returns null when no upcoming meeting exists', () => {
+    const now = new Date('2027-01-01T00:00:00Z')
+    const meetings = [meeting({ date_start: '2026-05-22T00:00:00+00:00' })]
+    expect(pickPreviewMeeting(meetings, now)).toBeNull()
+  })
+
+  it('skips cancelled meetings', () => {
+    const now = new Date('2026-01-01T00:00:00Z')
+    const meetings = [meeting({ is_cancelled: true })]
+    expect(pickPreviewMeeting(meetings, now)).toBeNull()
+  })
+
+  it('matches prior-year meeting by circuit_key', () => {
+    const prior = [
+      meeting({ meeting_key: 50, year: 2025, circuit_key: 10 }),
+      meeting({ meeting_key: 51, year: 2025, circuit_key: 20, meeting_name: 'Spain' }),
+    ]
+    expect(findPriorYearMeetingByCircuit(prior, 10)?.meeting_key).toBe(50)
+    expect(findPriorYearMeetingByCircuit(prior, 99)).toBeNull()
+    expect(findPriorYearMeetingByCircuit(prior, undefined)).toBeNull()
+  })
+
+  it('finds the grand prix race session', () => {
+    const sessions = [
+      session({ session_key: 1, session_name: 'FP1', session_type: 'Practice', date_start: '2026-05-22T10:00:00+00:00' }),
+      session({ session_key: 2, session_name: 'Sprint', session_type: 'Sprint', date_start: '2026-05-23T10:00:00+00:00' }),
+      session({ session_key: 3, session_name: 'Race', session_type: 'Race', date_start: '2026-05-24T13:00:00+00:00' }),
+    ]
+    expect(findRaceSession(sessions)?.session_key).toBe(3)
+  })
+
+  it('detects sprint weekends', () => {
+    const sprint = [
+      session({ session_type: 'Practice' }),
+      session({ session_name: 'Sprint', session_type: 'Sprint' }),
+      session({ session_type: 'Race' }),
+    ]
+    const normal = [session({ session_type: 'Practice' }), session({ session_type: 'Race' })]
+    expect(isSprintWeekend(sprint)).toBe(true)
+    expect(isSprintWeekend(normal)).toBe(false)
+  })
+
+  it('extracts podium and pole', () => {
+    const results: EnrichedResult[] = [
+      {
+        driver_number: 1,
+        position: 1,
+        name_acronym: 'VER',
+        full_name: 'Max Verstappen',
+        team_name: 'Red Bull',
+        team_colour: '3671c6',
+        dnf: false,
+        dns: false,
+        dsq: false,
+        duration: 100,
+        gap_to_leader: 0,
+        number_of_laps: 78,
+        points: 25,
+        session_key: 1,
+        meeting_key: 1,
+      },
+      {
+        driver_number: 4,
+        position: 2,
+        name_acronym: 'NOR',
+        full_name: 'Lando Norris',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        dnf: false,
+        dns: false,
+        dsq: false,
+        duration: 101,
+        gap_to_leader: 1,
+        number_of_laps: 78,
+        points: 18,
+        session_key: 1,
+        meeting_key: 1,
+      },
+      {
+        driver_number: 16,
+        position: 3,
+        name_acronym: 'LEC',
+        full_name: 'Charles Leclerc',
+        team_name: 'Ferrari',
+        team_colour: 'e8002d',
+        dnf: false,
+        dns: false,
+        dsq: false,
+        duration: 102,
+        gap_to_leader: 2,
+        number_of_laps: 78,
+        points: 15,
+        session_key: 1,
+        meeting_key: 1,
+      },
+    ]
+
+    const grid: EnrichedGrid[] = [
+      {
+        driver_number: 4,
+        position: 1,
+        name_acronym: 'NOR',
+        full_name: 'Lando Norris',
+        team_name: 'McLaren',
+        team_colour: 'ff8000',
+        session_key: 1,
+        meeting_key: 1,
+        lap_duration: 70,
+      },
+    ]
+
+    const podium = extractPodium(results)
+    expect(podium.map((p) => p.name_acronym)).toEqual(['VER', 'NOR', 'LEC'])
+    expect(extractPole(grid)?.name_acronym).toBe('NOR')
+  })
+
+  it('builds title fight gaps for top 3', () => {
+    const hub: ChampionshipHub = {
+      season: 2026,
+      round: 5,
+      total_rounds: 24,
+      rounds_left: 19,
+      last_race: 'Monaco GP',
+      round_labels: ['R1'],
+      drivers: [
+        hubDriver({ points: 200, position: 1 }),
+        hubDriver({ driver_number: 4, name_acronym: 'NOR', points: 160, position: 2 }),
+        hubDriver({ driver_number: 16, name_acronym: 'LEC', points: 120, position: 3 }),
+      ],
+      teams: [],
+    }
+
+    const rows = buildTitleFightContext(hub)
+    expect(rows).toHaveLength(3)
+    expect(rows[0].gapToLeader).toBe(0)
+    expect(rows[1].gapToLeader).toBe(40)
+    expect(rows[1].gapAfterRaceWin).toBe(15)
+    expect(rows[2].gapAfterSprintWeekendMax).toBe(200 - (120 + SPRINT_WEEKEND_MAX_POINTS))
+    expect(RACE_WIN_POINTS).toBe(25)
+  })
+
+  it('formats points gaps', () => {
+    expect(formatPointsGap(0)).toBe('LEADER')
+    expect(formatPointsGap(40)).toBe('+40')
+  })
+
+  it('picks countdown target as next future session', () => {
+    const sessions = [
+      session({ session_key: 1, session_name: 'FP1', session_type: 'Practice', date_start: '2026-05-22T10:00:00+00:00', date_end: '2026-05-22T11:00:00+00:00' }),
+      session({ session_key: 2, session_name: 'Race', session_type: 'Race', date_start: '2026-05-24T13:00:00+00:00', date_end: '2026-05-24T15:00:00+00:00' }),
+    ]
+    const now = new Date('2026-05-23T12:00:00Z')
+    expect(countdownTargetSession(sessions, now)?.session_key).toBe(2)
+  })
+})

frontend/src/test/replay.test.ts

@@ -0,0 +1,33 @@
+import { describe, expect, it } from 'vitest'
+import type { ReplayFrame, TrackBounds } from '../types'
+import { interpolateReplayCars, lookupReplayFramePair, replayCarToSvg } from '../lib/replay'
+
+const frames: ReplayFrame[] = [
+  { t: 0, cars: { '1': { x: 0, y: 0 } } },
+  { t: 5000, cars: { '1': { x: 10, y: 20 }, '4': { x: 40, y: 80 } } },
+  { t: 10000, cars: { '1': { x: 20, y: 40 } } },
+]
+
+describe('replay helpers', () => {
+  it('looks up boundary frame pairs', () => {
+    expect(lookupReplayFramePair(frames, -1)).toEqual({ previous: frames[0], next: frames[0] })
+    expect(lookupReplayFramePair(frames, 10000)).toEqual({ previous: frames[2], next: frames[2] })
+    expect(lookupReplayFramePair([], 1000)).toEqual({ previous: null, next: null })
+  })
+
+  it('interpolates cars between frames and keeps one-sided samples visible', () => {
+    const cars = interpolateReplayCars(frames, 2500)
+    expect(cars['1']).toEqual({ x: 5, y: 10 })
+    expect(cars['4']).toEqual({ x: 40, y: 80 })
+  })
+
+  it('clamps interpolation outside the replay range', () => {
+    expect(interpolateReplayCars(frames, -500)['1']).toEqual({ x: 0, y: 0 })
+    expect(interpolateReplayCars(frames, 12000)['1']).toEqual({ x: 20, y: 40 })
+  })
+
+  it('maps replay GPS through the shared track-map coordinate transform', () => {
+    const bounds: TrackBounds = { minX: 0, maxX: 100, minY: 0, maxY: 200 }
+    expect(replayCarToSvg({ x: 50, y: 50 }, bounds)).toEqual({ x: 50, y: 75 })
+  })
+})

frontend/src/test/replayMap.test.ts

@@ -0,0 +1,33 @@
+import { describe, expect, it } from 'vitest'
+import { isReplayMapAvailable } from '../lib/replayMap'
+import type { ReplayFramesResponse, TrackOutline } from '../types'
+
+const outline: TrackOutline = {
+  circuit_key: 1,
+  bounds: { minX: 0, maxX: 100, minY: 0, maxY: 100 },
+  points: [{ x: 0, y: 0 }],
+}
+
+const replay: ReplayFramesResponse = {
+  session_key: 1,
+  interval_ms: 5000,
+  start_time: '2025-05-25T13:00:00Z',
+  frames: [
+    { t: 0, cars: {} },
+    { t: 5000, cars: {} },
+  ],
+}
+
+describe('isReplayMapAvailable', () => {
+  it('returns true when frames and outline are present', () => {
+    expect(isReplayMapAvailable(replay, outline, false)).toBe(true)
+  })
+
+  it('returns false when frames are sparse', () => {
+    expect(isReplayMapAvailable({ ...replay, frames: [{ t: 0, cars: {} }] }, outline, false)).toBe(false)
+  })
+
+  it('returns false on query error', () => {
+    expect(isReplayMapAvailable(replay, outline, true)).toBe(false)
+  })
+})

frontend/src/test/rivalry.test.ts

@@ -0,0 +1,71 @@
+import { describe, it, expect } from 'vitest'
+import { gapSeries, h2hTally, lastRounds } from '../lib/rivalry'
+
+describe('gapSeries', () => {
+  it('computes per-round a − b', () => {
+    expect(gapSeries([25, 43, 68], [18, 36, 54])).toEqual([7, 7, 14])
+  })
+
+  it('handles negative gaps (b ahead)', () => {
+    expect(gapSeries([10, 20], [18, 36])).toEqual([-8, -16])
+  })
+
+  it('truncates to the shorter series', () => {
+    expect(gapSeries([25, 43, 68], [18])).toEqual([7])
+    expect(gapSeries([], [18, 36])).toEqual([])
+  })
+})
+
+describe('h2hTally', () => {
+  it('tallies lower-position wins per round', () => {
+    const t = h2hTally([1, 2, 1], [2, 1, 3], ['R1', 'R2', 'R3'])
+    expect(t.a).toBe(2)
+    expect(t.b).toBe(1)
+    expect(t.skipped).toBe(0)
+    expect(t.rounds.map((r) => r.winner)).toEqual(['a', 'b', 'a'])
+    expect(t.rounds[0]).toEqual({ round: 1, label: 'R1', posA: 1, posB: 2, winner: 'a' })
+  })
+
+  it('skips rounds where either driver has no position', () => {
+    // R2: a missing (0). R3: b missing (0). Only R1 and R4 count.
+    const t = h2hTally([1, 0, 5, 3], [4, 2, 0, 1], ['R1', 'R2', 'R3', 'R4'])
+    expect(t.a).toBe(1)
+    expect(t.b).toBe(1)
+    expect(t.skipped).toBe(2)
+    expect(t.rounds.map((r) => r.round)).toEqual([1, 4])
+  })
+
+  it('handles arrays of different lengths (missing tail = skipped)', () => {
+    const t = h2hTally([1, 2, 3], [2], ['R1', 'R2', 'R3'])
+    expect(t.a).toBe(1)
+    expect(t.b).toBe(0)
+    expect(t.skipped).toBe(2)
+  })
+
+  it('skips equal positions defensively and falls back on labels', () => {
+    const t = h2hTally([2, 1], [2, 3], ['R1'])
+    expect(t.a).toBe(1)
+    expect(t.b).toBe(0)
+    expect(t.skipped).toBe(1)
+    expect(t.rounds[0].label).toBe('R2')
+  })
+
+  it('returns an empty tally for empty inputs', () => {
+    const t = h2hTally([], [], [])
+    expect(t).toEqual({ a: 0, b: 0, rounds: [], skipped: 0 })
+  })
+})
+
+describe('lastRounds', () => {
+  it('returns the last n counted rounds in order', () => {
+    const t = h2hTally([1, 1, 1, 2, 1, 1, 2], [2, 2, 2, 1, 2, 2, 1], [])
+    const last = lastRounds(t, 5)
+    expect(last).toHaveLength(5)
+    expect(last.map((r) => r.round)).toEqual([3, 4, 5, 6, 7])
+  })
+
+  it('returns fewer when the tally has fewer counted rounds', () => {
+    const t = h2hTally([1, 0], [2, 0], [])
+    expect(lastRounds(t, 5)).toHaveLength(1)
+  })
+})

frontend/src/test/routeSearch.test.ts

@@ -0,0 +1,24 @@
+import { describe, it, expect } from 'vitest'
+import { parseRaceHubSearch, parseWeekendSearch, weekendFocusSearch } from '../lib/routeSearch'
+
+describe('routeSearch', () => {
+  it('parses positive weekend meeting/session keys and drops invalid values', () => {
+    expect(parseWeekendSearch({ meeting_key: '1229', session_key: '9000' })).toEqual({
+      meeting_key: 1229,
+      session_key: 9000,
+    })
+    expect(parseWeekendSearch({ meeting_key: '0', session_key: '-1', foo: 'bar' })).toEqual({})
+    expect(parseWeekendSearch({})).toEqual({})
+  })
+
+  it('parses race-hub session keys', () => {
+    expect(parseRaceHubSearch({ session_key: '9472' })).toEqual({ session_key: 9472 })
+    expect(parseRaceHubSearch({ session_key: 'nope' })).toEqual({})
+  })
+
+  it('builds Weekend focus search for Race Hub returns', () => {
+    expect(weekendFocusSearch(1229, 9000)).toEqual({ meeting_key: 1229, session_key: 9000 })
+    expect(weekendFocusSearch(null, 9000)).toEqual({ session_key: 9000 })
+    expect(weekendFocusSearch(1229, undefined)).toEqual({ meeting_key: 1229 })
+  })
+})

frontend/src/test/sessionState.test.ts

@@ -0,0 +1,146 @@
+import { describe, it, expect } from 'vitest'
+import {
+  resolveSessionState,
+  sessionState,
+  sessionStateLabel,
+} from '../lib/sessionState'
+import type {
+  ContextAvailability,
+  ContextSession,
+  DatasetInfo,
+  Session,
+  WeekendContext,
+  WeekendSession,
+} from '../types'
+
+const NOW = new Date('2025-06-01T00:00:00Z')
+
+function mk(
+  overrides: Partial<Session>,
+  source: WeekendSession['source'],
+  datasets: Record<string, DatasetInfo> = {},
+): WeekendSession {
+  return {
+    session: {
+      session_key: 1,
+      session_name: 'Race',
+      session_type: 'Race',
+      meeting_key: 1,
+      date_start: '2025-05-25T13:00:00+00:00',
+      date_end: '2025-05-25T15:00:00+00:00',
+      gmt_offset: '00:00:00',
+      ...overrides,
+    },
+    source,
+    datasets,
+  }
+}
+
+const FULL: Record<string, DatasetInfo> = Object.fromEntries(
+  [
+    'meeting',
+    'session',
+    'drivers',
+    'results',
+    'starting_grid',
+    'stints',
+    'pit_stops',
+    'positions',
+    'race_control',
+    'weather',
+    'laps',
+  ].map((k) => [k, { status: 'available', source: 'local', count: 1 }]),
+)
+
+function availability(overrides: Partial<ContextAvailability> = {}): ContextAvailability {
+  return {
+    schedule: 'available',
+    live_transport: 'unknown',
+    live_session: 'inactive',
+    archive: 'unavailable',
+    local_analysis: 'complete',
+    freshness: 'fresh',
+    limitations: [],
+    ...overrides,
+  }
+}
+
+function contextSession(
+  session: Session,
+  avail: Partial<ContextAvailability> = {},
+): ContextSession {
+  return { session, availability: availability(avail) }
+}
+
+function context(overrides: Partial<WeekendContext> = {}): WeekendContext {
+  return {
+    temporal_state: 'post_weekend',
+    championship_round: 1,
+    total_championship_rounds: 1,
+    ...overrides,
+  }
+}
+
+describe('sessionState', () => {
+  it('marks a future session as upcoming', () => {
+    const s = mk({ date_start: '2099-05-25T13:00:00+00:00', date_end: '2099-05-25T15:00:00+00:00' }, 'none')
+    expect(sessionState(s, NOW)).toBe('upcoming')
+  })
+
+  it('does not mark Live from schedule alone', () => {
+    const start = new Date(NOW.getTime() - 60_000).toISOString()
+    const end = new Date(NOW.getTime() + 60_000).toISOString()
+    const s = mk({ date_start: start, date_end: end }, 'none')
+    expect(sessionState(s, NOW)).toBe('preparing')
+  })
+
+  it('marks Live only when Weekend Context active identity matches', () => {
+    const start = new Date(NOW.getTime() - 60_000).toISOString()
+    const end = new Date(NOW.getTime() + 60_000).toISOString()
+    const s = mk({ session_key: 42, date_start: start, date_end: end }, 'none')
+    const ctx = context({
+      temporal_state: 'session_live',
+      active_session: contextSession(s.session, { live_session: 'active' }),
+    })
+    expect(resolveSessionState({ weekendSession: s, context: ctx, now: NOW })).toBe('live')
+  })
+
+  it('marks a finished session with full local data as ready', () => {
+    const s = mk({}, 'local', FULL)
+    expect(sessionState(s, NOW)).toBe('ready')
+  })
+
+  it('marks a finished session with no data as preparing', () => {
+    const s = mk({}, 'none', {})
+    expect(sessionState(s, NOW)).toBe('preparing')
+  })
+
+  it('marks a finished session with partial data as partial', () => {
+    const s = mk({}, 'partial', { drivers: { status: 'available', source: 'local', count: 20 } })
+    expect(sessionState(s, NOW)).toBe('partial')
+  })
+
+  it('marks unavailable from context availability', () => {
+    const s = mk({ session_key: 7 }, 'none')
+    const ctx = context({
+      previous_completed_session: contextSession(s.session, {
+        local_analysis: 'unavailable',
+      }),
+    })
+    expect(resolveSessionState({ weekendSession: s, context: ctx, now: NOW })).toBe(
+      'unavailable',
+    )
+  })
+
+  it('marks a cancelled session as cancelled', () => {
+    const s = mk({}, 'cancelled')
+    expect(sessionState(s, NOW)).toBe('cancelled')
+  })
+
+  it('uses user language labels rather than coverage counts', () => {
+    expect(sessionStateLabel('ready')).toBe('Ready')
+    expect(sessionStateLabel('upcoming')).toBe('Upcoming')
+    expect(sessionStateLabel('partial')).toBe('Partial')
+    expect(sessionStateLabel('unavailable')).toBe('Unavailable')
+  })
+})

frontend/src/test/simulator.test.ts

@@ -29,6 +29,7 @@ function driver(over: Partial<ChampHubDriver>): ChampHubDriver {
     poles: 0,
     form: [],
     cumulative: [],
+    round_positions: [],
     teammate_wins: 0,
     teammate_losses: 0,
     ...over,

frontend/src/test/weekendContext.test.ts

@@ -0,0 +1,223 @@
+import { describe, it, expect } from 'vitest'
+import {
+  analysisSessionKey,
+  briefingItems,
+  championshipImpact,
+  hasLocalAnalysis,
+  meetingIdentity,
+  podiumFromResults,
+  resolveViewState,
+} from '../lib/weekendContext'
+import type {
+  ChampionshipHub,
+  ContextAvailability,
+  ContextSession,
+  EnrichedResult,
+  Meeting,
+  NewsItem,
+  Session,
+  TemporalState,
+  WeekendContext,
+} from '../types'
+
+function availability(overrides: Partial<ContextAvailability> = {}): ContextAvailability {
+  return {
+    schedule: 'available',
+    live_transport: 'unknown',
+    live_session: 'inactive',
+    archive: 'unavailable',
+    local_analysis: 'complete',
+    freshness: 'fresh',
+    limitations: [],
+    ...overrides,
+  }
+}
+
+function meeting(overrides: Partial<Meeting> = {}): Meeting {
+  return {
+    meeting_key: 1,
+    meeting_name: 'British Grand Prix',
+    meeting_official_name: 'FORMULA 1 BRITISH GRAND PRIX',
+    location: 'Silverstone',
+    country_name: 'United Kingdom',
+    country_code: 'GBR',
+    country_flag: '',
+    circuit_key: 2,
+    circuit_short_name: 'Silverstone',
+    date_start: '2026-07-03T09:00:00Z',
+    date_end: '2026-07-05T16:00:00Z',
+    year: 2026,
+    ...overrides,
+  }
+}
+
+function session(overrides: Partial<Session> = {}): Session {
+  return {
+    session_key: 11,
+    session_name: 'Race',
+    session_type: 'Race',
+    meeting_key: 1,
+    date_start: '2026-07-05T14:00:00Z',
+    date_end: '2026-07-05T16:00:00Z',
+    gmt_offset: '',
+    ...overrides,
+  }
+}
+
+function ctxSession(overrides: Partial<ContextSession> = {}): ContextSession {
+  return {
+    session: session(),
+    meeting: meeting(),
+    availability: availability(),
+    ...overrides,
+  }
+}
+
+function context(overrides: Partial<WeekendContext> = {}): WeekendContext {
+  return {
+    season: 2026,
+    temporal_state: 'between_weekends',
+    championship_round: 1,
+    total_championship_rounds: 24,
+    ...overrides,
+  }
+}
+
+describe('resolveViewState', () => {
+  const cases: Array<[TemporalState, string]> = [
+    ['no_season', 'no_season'],
+    ['between_weekends', 'between_weekends'],
+    ['pre_session', 'pre_session'],
+    ['session_live', 'session_live'],
+    ['session_settling', 'session_settling'],
+    ['between_sessions', 'between_sessions'],
+    ['post_weekend', 'post_weekend'],
+    ['season_complete', 'season_complete'],
+  ]
+
+  it.each(cases)('maps canonical temporal_state %s to view %s', (temporal, expected) => {
+    expect(resolveViewState(context({ temporal_state: temporal }))).toBe(expected)
+  })
+
+  it('treats an unknown/absent temporal_state as no_season rather than inventing a state', () => {
+    expect(resolveViewState(context({ temporal_state: 'garbage' as TemporalState }))).toBe('no_season')
+  })
+})
+
+describe('analysisSessionKey', () => {
+  it('prefers the default analysis session', () => {
+    const ctx = context({
+      default_analysis_session: ctxSession({ session: session({ session_key: 32 }) }),
+      previous_completed_session: ctxSession({ session: session({ session_key: 11 }) }),
+    })
+    expect(analysisSessionKey(ctx)).toBe(32)
+  })
+
+  it('falls back to the previous completed session', () => {
+    const ctx = context({
+      previous_completed_session: ctxSession({ session: session({ session_key: 11 }) }),
+    })
+    expect(analysisSessionKey(ctx)).toBe(11)
+  })
+
+  it('returns undefined when there is no analysable session', () => {
+    expect(analysisSessionKey(context())).toBeUndefined()
+  })
+
+  it('returns undefined for a zero/synthetic session key', () => {
+    const ctx = context({
+      previous_completed_session: ctxSession({ session: session({ session_key: 0 }) }),
+    })
+    expect(analysisSessionKey(ctx)).toBeUndefined()
+  })
+})
+
+describe('hasLocalAnalysis', () => {
+  it('is true for complete or partial local analysis', () => {
+    expect(hasLocalAnalysis(ctxSession({ availability: availability({ local_analysis: 'complete' }) }))).toBe(true)
+    expect(hasLocalAnalysis(ctxSession({ availability: availability({ local_analysis: 'partial' }) }))).toBe(true)
+  })
+
+  it('is false for pending/not_applicable/absent', () => {
+    expect(hasLocalAnalysis(ctxSession({ availability: availability({ local_analysis: 'pending' }) }))).toBe(false)
+    expect(hasLocalAnalysis(ctxSession({ availability: availability({ local_analysis: 'not_applicable' }) }))).toBe(false)
+    expect(hasLocalAnalysis(undefined)).toBe(false)
+  })
+})
+
+describe('meetingIdentity', () => {
+  it('derives a short name and tolerates partial fields', () => {
+    const id = meetingIdentity(meeting({ meeting_name: 'Monaco Grand Prix', circuit_short_name: '', location: 'Monaco' }))
+    expect(id?.short_name).toBe('Monaco')
+    expect(id?.circuit_short_name).toBe('Monaco')
+  })
+
+  it('returns undefined for an absent meeting', () => {
+    expect(meetingIdentity(undefined)).toBeUndefined()
+  })
+
+  it('drops empty date strings', () => {
+    const id = meetingIdentity(meeting({ date_start: '', date_end: '' }))
+    expect(id?.date_start).toBeUndefined()
+    expect(id?.date_end).toBeUndefined()
+  })
+})
+
+describe('championshipImpact', () => {
+  const hub: ChampionshipHub = {
+    season: 2026,
+    round: 2,
+    total_rounds: 24,
+    rounds_left: 22,
+    last_race: 'British GP',
+    round_labels: ['R1', 'R2'],
+    drivers: [
+      { driver_number: 1, name_acronym: 'VER', full_name: 'Max', team_name: 'RB', team_colour: '3671c6', points: 50, position: 1, wins: 2, podiums: 2, poles: 1, form: [], cumulative: [25, 50], teammate_wins: 0, teammate_losses: 0, round_positions: [] },
+      { driver_number: 4, name_acronym: 'NOR', full_name: 'Lando', team_name: 'McL', team_colour: 'ff8000', points: 40, position: 2, wins: 1, podiums: 2, poles: 0, form: [], cumulative: [18, 40], teammate_wins: 0, teammate_losses: 0, round_positions: [] },
+    ],
+    teams: [],
+  }
+
+  it('maps top-3 movers with deltas and a note', () => {
+    const impact = championshipImpact(hub)
+    expect(impact?.leaders).toHaveLength(2)
+    expect(impact?.leaders[0].delta).toBe(25)
+    expect(impact?.note).toContain('British GP')
+  })
+
+  it('returns undefined for an empty hub', () => {
+    expect(championshipImpact(undefined)).toBeUndefined()
+    expect(championshipImpact({ ...hub, drivers: [] })).toBeUndefined()
+  })
+})
+
+describe('briefingItems', () => {
+  it('caps at three items and maps fields', () => {
+    const news: NewsItem[] = Array.from({ length: 5 }, (_, i) => ({
+      source: 'src',
+      title: `Item ${i}`,
+      url: `https://x/${i}`,
+      fetched_at: '2026-07-06T00:00:00Z',
+      category: 'news',
+      og_image_url: 'img',
+    }))
+    const items = briefingItems(news)
+    expect(items).toHaveLength(3)
+    expect(items[0]).toMatchObject({ title: 'Item 0', image_url: 'img' })
+  })
+})
+
+describe('podiumFromResults', () => {
+  it('sorts by position, caps at three, and formats gaps', () => {
+    const results: EnrichedResult[] = [
+      { driver_number: 44, position: 2, name_acronym: 'HAM', full_name: 'Lewis', team_name: 'Ferrari', team_colour: 'e8002d', dnf: false, dns: false, dsq: false, duration: null, gap_to_leader: 5.123 } as EnrichedResult,
+      { driver_number: 1, position: 1, name_acronym: 'VER', full_name: 'Max', team_name: 'RB', team_colour: '3671c6', dnf: false, dns: false, dsq: false, duration: 5400, gap_to_leader: null } as EnrichedResult,
+      { driver_number: 16, position: 3, name_acronym: 'LEC', full_name: 'Charles', team_name: 'Ferrari', team_colour: 'e8002d', dnf: false, dns: false, dsq: false, duration: null, gap_to_leader: '+10.5' } as EnrichedResult,
+      { driver_number: 55, position: 4, name_acronym: 'SAI', full_name: 'Carlos', team_name: 'W', team_colour: 'fff', dnf: false, dns: false, dsq: false, duration: null, gap_to_leader: 20 } as EnrichedResult,
+    ]
+    const podium = podiumFromResults(results)
+    expect(podium.map((p) => p.name_acronym)).toEqual(['VER', 'HAM', 'LEC'])
+    expect(podium[1].gap).toBe('+5.123')
+    expect(podium[2].gap).toBe('+10.5')
+  })
+})

frontend/src/types.ts

@@ -12,6 +12,7 @@ export interface Meeting {
   country_name: string
   country_code: string
   country_flag: string
+  circuit_key?: number
   circuit_short_name: string
   date_start: string
   date_end: string
@@ -23,6 +24,7 @@ export interface Session {
   session_key: number
   session_name: string
   session_type: string
+  circuit_key?: number
   meeting_key: number
   date_start: string
   date_end: string
@@ -89,6 +91,18 @@ export interface RaceHub {
   race_control: RaceControlMessage[]
   weather: WeatherSample[]
   laps: Lap[]
+  chapters: Chapter[]
+}
+
+export interface Chapter {
+  kind: 'start' | 'safety_car' | 'virtual_safety_car' | 'red_flag' | 'pit_phase' | 'decisive_swing' | 'finish' | string
+  title: string
+  headline: string
+  start_lap: number
+  end_lap: number
+  start_time?: string
+  end_time?: string
+  driver_numbers: number[]
 }
 
 export interface Stint {
@@ -347,6 +361,23 @@ export interface TrackOutline {
   bounds: TrackBounds
 }
 
+export interface ReplayCarPosition {
+  x: number
+  y: number
+}
+
+export interface ReplayFrame {
+  t: number
+  cars: Record<string, ReplayCarPosition>
+}
+
+export interface ReplayFramesResponse {
+  session_key: number
+  interval_ms: number
+  start_time: string
+  frames: ReplayFrame[]
+}
+
 export interface ChampHubDriver {
   driver_number: number
   name_acronym: string
@@ -360,6 +391,7 @@ export interface ChampHubDriver {
   poles: number
   form: number[]
   cumulative: number[]
+  round_positions: number[]
   teammate_wins: number
   teammate_losses: number
 }
@@ -383,6 +415,140 @@ export interface ChampionshipHub {
   teams: ChampHubTeam[]
 }
 
+export interface DriverSummaryRound {
+  meeting_key: number
+  meeting_name: string
+  country_code: string
+  country_name: string
+  race_position: number
+  grid_position: number
+  quali_position?: number
+  points: number
+  dnf: boolean
+  dns: boolean
+  dsq: boolean
+}
+
+export interface DriverSummary {
+  season: number
+  driver_number: number
+  name_acronym: string
+  full_name: string
+  team_name: string
+  team_colour: string
+  headshot_url: string
+  points: number
+  position: number
+  wins: number
+  podiums: number
+  poles: number
+  form: number[]
+  cumulative: number[]
+  round_labels: string[]
+  rounds: DriverSummaryRound[]
+}
+
+// ── Weekend Context ──
+// Canonical local-first contract for the adaptive Weekend home, served verbatim
+// by /api/v1/weekend-context (backend story #72, internal/query/context.go).
+// The frontend consumes this shape as the single source of truth; view-model
+// derivation lives in lib/weekendContext.ts.
+
+// TemporalState mirrors query.TemporalState exactly (the JSON `temporal_state`).
+export type TemporalState =
+  | 'no_season'
+  | 'between_weekends'
+  | 'pre_session'
+  | 'session_live'
+  | 'session_settling'
+  | 'between_sessions'
+  | 'post_weekend'
+  | 'season_complete'
+
+// ContextAvailability mirrors query.ContextAvailability. Every field is present
+// in a canonical payload except the optional `observed_at`.
+export interface ContextAvailability {
+  schedule: string
+  live_transport: string
+  live_session: string
+  archive: string
+  local_analysis: string
+  freshness: string
+  observed_at?: string
+  limitations: string[]
+}
+
+// ContextSession mirrors query.ContextSession: a session identity coupled with
+// its meeting and structured availability contract.
+export interface ContextSession {
+  session: Session
+  meeting?: Meeting
+  availability: ContextAvailability
+}
+
+// WeekendContext mirrors query.WeekendContext (the canonical endpoint body).
+export interface WeekendContext {
+  season?: number
+  temporal_state: TemporalState
+  previous_meeting?: Meeting
+  focus_meeting?: Meeting
+  next_meeting?: Meeting
+  previous_completed_session?: ContextSession
+  active_session?: ContextSession
+  next_session?: ContextSession
+  default_analysis_session?: ContextSession
+  championship_round: number
+  total_championship_rounds: number
+}
+
+// ── Weekend view model (client-only) ──
+// The rendered Weekend home layers a small set of non-canonical UI states
+// (loading/error) plus supplementary data (championship movers, briefing) on top
+// of the canonical context. None of these are part of the #72 contract.
+export type WeekendViewState =
+  | 'loading'
+  | 'error'
+  | 'no_season'
+  | 'between_weekends'
+  | 'pre_session'
+  | 'session_live'
+  | 'session_settling'
+  | 'between_sessions'
+  | 'post_weekend'
+  | 'season_complete'
+
+export interface WeekendChampionshipMover {
+  position: number
+  driver_number: number
+  name_acronym: string
+  team_colour: string
+  points: number
+  delta?: number
+}
+
+export interface WeekendChampionshipImpact {
+  leaders: WeekendChampionshipMover[]
+  note?: string
+}
+
+export interface WeekendBriefingItem {
+  category?: string
+  title: string
+  url: string
+  source: string
+  published_at?: string
+  image_url?: string
+}
+
+export interface WeekendPodiumEntry {
+  position: number
+  driver_number: number
+  name_acronym: string
+  team_name: string
+  team_colour: string
+  gap: string
+}
+
 export interface NewsItem {
   source: string
   title: string

internal/chapters/chapters.go

@@ -0,0 +1,629 @@
+package chapters
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/AmanTahiliani/box-box/internal/models"
+)
+
+const (
+	KindStart            = "start"
+	KindSafetyCar        = "safety_car"
+	KindVirtualSafetyCar = "virtual_safety_car"
+	KindRedFlag          = "red_flag"
+	KindPitPhase         = "pit_phase"
+	KindDecisiveSwing    = "decisive_swing"
+	KindFinish           = "finish"
+
+	pitPhaseWindowLaps = 3
+	pitPhaseShare      = 0.30
+	minPitPhaseStops   = 2
+	maxDecisiveSwings  = 3
+	decisiveAfterLap   = 5
+	structuralPriority = 110
+	flagPriority       = 100
+	pitPhasePriority   = 50
+	decisivePriority   = 40
+)
+
+type RaceControl = models.RaceControl
+type PositionSample = models.Position
+type Lap = models.Lap
+
+// Chapter is a deterministic replay segment derived from timing and race-control data.
+type Chapter struct {
+	Kind          string `json:"kind"`
+	Title         string `json:"title"`
+	Headline      string `json:"headline"`
+	StartLap      int    `json:"start_lap"`
+	EndLap        int    `json:"end_lap"`
+	StartTime     string `json:"start_time,omitempty"`
+	EndTime       string `json:"end_time,omitempty"`
+	DriverNumbers []int  `json:"driver_numbers"`
+}
+
+// Detect builds replay chapters from already-loaded race-hub datasets.
+func Detect(rc []RaceControl, positions []PositionSample, laps []Lap, totalLaps int) []Chapter {
+	totalLaps = normalizeTotalLaps(totalLaps, laps, rc)
+	if totalLaps <= 0 && len(rc) == 0 && len(positions) == 0 && len(laps) == 0 {
+		return []Chapter{}
+	}
+	if totalLaps <= 0 {
+		totalLaps = 1
+	}
+
+	lapIndex := buildLapIndex(laps)
+	chapters := []Chapter{
+		{
+			Kind:      KindStart,
+			Title:     "Start",
+			StartLap:  1,
+			EndLap:    minInt(1, totalLaps),
+			StartTime: lapIndex.lapStart(1),
+			EndTime:   lapIndex.lapEnd(1),
+		},
+	}
+	chapters = append(chapters, detectFlagPeriods(rc, lapIndex, totalLaps)...)
+	chapters = append(chapters, detectPitPhases(laps, lapIndex)...)
+	chapters = append(chapters, detectDecisiveSwings(positions, lapIndex, totalLaps)...)
+	chapters = append(chapters, detectFinish(rc, lapIndex, totalLaps))
+
+	return resolveConflicts(chapters)
+}
+
+func normalizeTotalLaps(totalLaps int, laps []Lap, rc []RaceControl) int {
+	for _, l := range laps {
+		if l.LapNumber > totalLaps {
+			totalLaps = l.LapNumber
+		}
+	}
+	for _, msg := range rc {
+		if msg.LapNumber != nil && *msg.LapNumber > totalLaps {
+			totalLaps = *msg.LapNumber
+		}
+	}
+	return totalLaps
+}
+
+type lapIndex struct {
+	byLap  map[int]string
+	events []lapEvent
+}
+
+type lapEvent struct {
+	lap int
+	at  time.Time
+}
+
+func buildLapIndex(laps []Lap) lapIndex {
+	idx := lapIndex{byLap: map[int]string{}}
+	for _, l := range laps {
+		if l.LapNumber <= 0 || l.DateStart == "" {
+			continue
+		}
+		if _, ok := idx.byLap[l.LapNumber]; !ok {
+			idx.byLap[l.LapNumber] = l.DateStart
+		}
+		at, ok := parseTime(l.DateStart)
+		if ok {
+			idx.events = append(idx.events, lapEvent{lap: l.LapNumber, at: at})
+		}
+	}
+	sort.Slice(idx.events, func(i, j int) bool {
+		if idx.events[i].at.Equal(idx.events[j].at) {
+			return idx.events[i].lap < idx.events[j].lap
+		}
+		return idx.events[i].at.Before(idx.events[j].at)
+	})
+	return idx
+}
+
+func (idx lapIndex) lapStart(lap int) string {
+	return idx.byLap[lap]
+}
+
+func (idx lapIndex) lapEnd(lap int) string {
+	if v := idx.byLap[lap+1]; v != "" {
+		return v
+	}
+	return idx.byLap[lap]
+}
+
+func (idx lapIndex) lapForTime(raw string) int {
+	at, ok := parseTime(raw)
+	if !ok || len(idx.events) == 0 {
+		return 0
+	}
+	lap := 0
+	for _, event := range idx.events {
+		if event.at.After(at) {
+			break
+		}
+		lap = event.lap
+	}
+	if lap == 0 {
+		return idx.events[0].lap
+	}
+	return lap
+}
+
+type flagState struct {
+	startLap  int
+	startTime string
+}
+
+func detectFlagPeriods(rc []RaceControl, idx lapIndex, totalLaps int) []Chapter {
+	var chapters []Chapter
+	active := map[string]flagState{}
+	for _, msg := range rc {
+		kind, ok := flagKind(msg)
+		if !ok && greenFlagClear(msg) {
+			for activeKind, st := range active {
+				lap := messageLap(msg, idx)
+				if lap <= 0 {
+					lap = st.startLap
+				}
+				endLap := clampLap(lap, st.startLap, totalLaps)
+				chapters = append(chapters, Chapter{
+					Kind:      activeKind,
+					Title:     flagTitle(activeKind, st.startLap, endLap),
+					StartLap:  st.startLap,
+					EndLap:    endLap,
+					StartTime: st.startTime,
+					EndTime:   firstNonEmpty(msg.Date, idx.lapEnd(endLap)),
+				})
+				delete(active, activeKind)
+			}
+			continue
+		}
+		if !ok {
+			continue
+		}
+		lap := messageLap(msg, idx)
+		if lap <= 0 {
+			lap = 1
+		}
+		if flagCleared(msg) {
+			st, ok := active[kind]
+			if !ok {
+				continue
+			}
+			endLap := clampLap(lap, st.startLap, totalLaps)
+			chapters = append(chapters, Chapter{
+				Kind:      kind,
+				Title:     flagTitle(kind, st.startLap, endLap),
+				StartLap:  st.startLap,
+				EndLap:    endLap,
+				StartTime: st.startTime,
+				EndTime:   firstNonEmpty(msg.Date, idx.lapEnd(endLap)),
+			})
+			delete(active, kind)
+			continue
+		}
+		if flagStarted(msg) {
+			active[kind] = flagState{
+				startLap:  clampLap(lap, 1, totalLaps),
+				startTime: firstNonEmpty(msg.Date, idx.lapStart(lap)),
+			}
+		}
+	}
+	for kind, st := range active {
+		endLap := totalLaps
+		chapters = append(chapters, Chapter{
+			Kind:      kind,
+			Title:     flagTitle(kind, st.startLap, endLap),
+			StartLap:  st.startLap,
+			EndLap:    endLap,
+			StartTime: st.startTime,
+			EndTime:   idx.lapEnd(endLap),
+		})
+	}
+	return chapters
+}
+
+func flagKind(msg RaceControl) (string, bool) {
+	text := upperText(string(msg.Category), string(msg.Flag), msg.Message)
+	if strings.Contains(text, "VSC") || strings.Contains(text, "VIRTUAL SAFETY CAR") {
+		return KindVirtualSafetyCar, true
+	}
+	if strings.Contains(text, "RED FLAG") || string(msg.Flag) == string(models.FlagRed) {
+		return KindRedFlag, true
+	}
+	if strings.Contains(text, "SAFETY CAR") || msg.Category == models.CategorySafetyCar {
+		return KindSafetyCar, true
+	}
+	return "", false
+}
+
+func flagStarted(msg RaceControl) bool {
+	text := upperText(string(msg.Category), string(msg.Flag), msg.Message)
+	if strings.Contains(text, "CLEAR") || strings.Contains(text, "ENDING") || strings.Contains(text, "IN THIS LAP") || strings.Contains(text, "GREEN") {
+		return false
+	}
+	return strings.Contains(text, "DEPLOY") ||
+		strings.Contains(text, "RED FLAG") ||
+		strings.Contains(text, "VIRTUAL SAFETY CAR") ||
+		strings.Contains(text, "VSC") ||
+		strings.Contains(text, "SAFETY CAR") ||
+		string(msg.Flag) == string(models.FlagRed)
+}
+
+func flagCleared(msg RaceControl) bool {
+	text := upperText(string(msg.Category), string(msg.Flag), msg.Message)
+	return strings.Contains(text, "CLEAR") ||
+		strings.Contains(text, "ENDING") ||
+		strings.Contains(text, "IN THIS LAP") ||
+		strings.Contains(text, "GREEN")
+}
+
+func greenFlagClear(msg RaceControl) bool {
+	text := upperText(string(msg.Flag), msg.Message)
+	return strings.Contains(text, "GREEN")
+}
+
+func flagTitle(kind string, startLap, endLap int) string {
+	name := "Flag period"
+	switch kind {
+	case KindSafetyCar:
+		name = "Safety Car"
+	case KindVirtualSafetyCar:
+		name = "Virtual Safety Car"
+	case KindRedFlag:
+		name = "Red Flag"
+	}
+	return fmt.Sprintf("%s (L%d-L%d)", name, startLap, endLap)
+}
+
+func detectPitPhases(laps []Lap, idx lapIndex) []Chapter {
+	type pitOut struct {
+		lap    int
+		driver int
+	}
+	var stops []pitOut
+	for _, l := range laps {
+		if l.IsPitOutLap && l.LapNumber > 0 {
+			stops = append(stops, pitOut{lap: l.LapNumber, driver: l.DriverNumber})
+		}
+	}
+	if len(stops) < minPitPhaseStops {
+		return nil
+	}
+	sort.Slice(stops, func(i, j int) bool {
+		if stops[i].lap == stops[j].lap {
+			return stops[i].driver < stops[j].driver
+		}
+		return stops[i].lap < stops[j].lap
+	})
+	needed := int(math.Ceil(float64(len(stops)) * pitPhaseShare))
+	if needed < minPitPhaseStops {
+		needed = minPitPhaseStops
+	}
+
+	var windows []Chapter
+	for i := 0; i < len(stops); i++ {
+		start := stops[i].lap
+		end := start + pitPhaseWindowLaps - 1
+		drivers := map[int]bool{}
+		count := 0
+		for _, stop := range stops {
+			if stop.lap < start || stop.lap > end {
+				continue
+			}
+			count++
+			drivers[stop.driver] = true
+		}
+		if count < needed {
+			continue
+		}
+		ch := Chapter{
+			Kind:          KindPitPhase,
+			Title:         fmt.Sprintf("Pit phase (L%d-L%d)", start, end),
+			StartLap:      start,
+			EndLap:        end,
+			StartTime:     idx.lapStart(start),
+			EndTime:       idx.lapEnd(end),
+			DriverNumbers: sortedDriverNumbers(drivers),
+		}
+		if len(windows) > 0 && ch.StartLap <= windows[len(windows)-1].EndLap+1 {
+			last := &windows[len(windows)-1]
+			if ch.EndLap > last.EndLap {
+				last.EndLap = ch.EndLap
+				last.EndTime = idx.lapEnd(last.EndLap)
+			}
+			drivers := sliceToSet(last.DriverNumbers)
+			for _, driver := range ch.DriverNumbers {
+				drivers[driver] = true
+			}
+			last.DriverNumbers = sortedDriverNumbers(drivers)
+			last.Title = fmt.Sprintf("Pit phase (L%d-L%d)", last.StartLap, last.EndLap)
+			continue
+		}
+		windows = append(windows, ch)
+	}
+	return windows
+}
+
+type swingCandidate struct {
+	chapter      Chapter
+	significance int
+}
+
+func detectDecisiveSwings(positions []PositionSample, idx lapIndex, totalLaps int) []Chapter {
+	if len(positions) == 0 || len(idx.events) == 0 || totalLaps <= decisiveAfterLap {
+		return nil
+	}
+	snapshots := buildPositionSnapshots(positions, idx, totalLaps)
+	if len(snapshots) == 0 {
+		return nil
+	}
+	final := snapshots[totalLaps]
+	if len(final) == 0 {
+		for lap := totalLaps - 1; lap >= 1; lap-- {
+			if len(snapshots[lap]) > 0 {
+				final = snapshots[lap]
+				break
+			}
+		}
+	}
+	var candidates []swingCandidate
+	seenDriver := map[int]bool{}
+	for lap := decisiveAfterLap + 1; lap <= totalLaps; lap++ {
+		prev := snapshots[lap-1]
+		curr := snapshots[lap]
+		if len(prev) == 0 || len(curr) == 0 {
+			continue
+		}
+		for driver, pos := range curr {
+			prevPos, ok := prev[driver]
+			if !ok || prevPos <= pos || pos > 5 || pos <= 0 || seenDriver[driver] {
+				continue
+			}
+			finalPos, ok := final[driver]
+			if !ok || finalPos > pos {
+				continue
+			}
+			overtaken := driverAtPosition(curr, prevPos, driver)
+			drivers := []int{driver}
+			if overtaken != 0 {
+				drivers = append(drivers, overtaken)
+			}
+			candidates = append(candidates, swingCandidate{
+				chapter: Chapter{
+					Kind:          KindDecisiveSwing,
+					Title:         fmt.Sprintf("Decisive swing: #%d to P%d (L%d)", driver, pos, lap),
+					StartLap:      lap,
+					EndLap:        lap,
+					StartTime:     idx.lapStart(lap),
+					EndTime:       idx.lapEnd(lap),
+					DriverNumbers: drivers,
+				},
+				significance: (prevPos-pos)*10 + (6 - pos),
+			})
+			seenDriver[driver] = true
+		}
+	}
+	sort.Slice(candidates, func(i, j int) bool {
+		if candidates[i].significance == candidates[j].significance {
+			return candidates[i].chapter.StartLap < candidates[j].chapter.StartLap
+		}
+		return candidates[i].significance > candidates[j].significance
+	})
+	if len(candidates) > maxDecisiveSwings {
+		candidates = candidates[:maxDecisiveSwings]
+	}
+	out := make([]Chapter, 0, len(candidates))
+	for _, c := range candidates {
+		out = append(out, c.chapter)
+	}
+	return out
+}
+
+func buildPositionSnapshots(positions []PositionSample, idx lapIndex, totalLaps int) map[int]map[int]int {
+	byLap := map[int][]PositionSample{}
+	for _, p := range positions {
+		if p.Position <= 0 {
+			continue
+		}
+		lap := idx.lapForTime(p.Date)
+		if lap <= 0 || lap > totalLaps {
+			continue
+		}
+		byLap[lap] = append(byLap[lap], p)
+	}
+	last := map[int]int{}
+	snapshots := map[int]map[int]int{}
+	for lap := 1; lap <= totalLaps; lap++ {
+		for _, p := range byLap[lap] {
+			last[p.DriverNumber] = p.Position
+		}
+		if len(last) == 0 {
+			continue
+		}
+		cp := make(map[int]int, len(last))
+		for driver, pos := range last {
+			cp[driver] = pos
+		}
+		snapshots[lap] = cp
+	}
+	return snapshots
+}
+
+func driverAtPosition(snapshot map[int]int, pos int, exclude int) int {
+	for driver, driverPos := range snapshot {
+		if driver != exclude && driverPos == pos {
+			return driver
+		}
+	}
+	return 0
+}
+
+func detectFinish(rc []RaceControl, idx lapIndex, totalLaps int) Chapter {
+	finishLap := totalLaps
+	finishTime := idx.lapEnd(totalLaps)
+	for _, msg := range rc {
+		text := upperText(string(msg.Flag), msg.Message)
+		if strings.Contains(text, "CHEQUER") || string(msg.Flag) == string(models.FlagChequered) {
+			if lap := messageLap(msg, idx); lap > 0 {
+				finishLap = lap
+			}
+			finishTime = firstNonEmpty(msg.Date, finishTime)
+		}
+	}
+	startLap := finishLap - 1
+	if startLap < 1 {
+		startLap = 1
+	}
+	return Chapter{
+		Kind:      KindFinish,
+		Title:     fmt.Sprintf("Finish (L%d-L%d)", startLap, finishLap),
+		StartLap:  startLap,
+		EndLap:    finishLap,
+		StartTime: idx.lapStart(startLap),
+		EndTime:   finishTime,
+	}
+}
+
+func resolveConflicts(chapters []Chapter) []Chapter {
+	normalized := make([]Chapter, 0, len(chapters))
+	for _, ch := range chapters {
+		if ch.StartLap <= 0 {
+			ch.StartLap = 1
+		}
+		if ch.EndLap <= 0 {
+			ch.EndLap = ch.StartLap
+		}
+		if ch.EndLap < ch.StartLap {
+			ch.EndLap = ch.StartLap
+		}
+		if ch.DriverNumbers == nil {
+			ch.DriverNumbers = []int{}
+		}
+		normalized = append(normalized, ch)
+	}
+	sort.SliceStable(normalized, func(i, j int) bool {
+		if normalized[i].StartLap == normalized[j].StartLap {
+			return priority(normalized[i].Kind) > priority(normalized[j].Kind)
+		}
+		return normalized[i].StartLap < normalized[j].StartLap
+	})
+
+	out := make([]Chapter, 0, len(normalized))
+	for _, ch := range normalized {
+		if len(out) == 0 {
+			out = append(out, ch)
+			continue
+		}
+		last := &out[len(out)-1]
+		if ch.StartLap > last.EndLap {
+			out = append(out, ch)
+			continue
+		}
+		if isFlag(last.Kind) && priority(ch.Kind) < priority(last.Kind) {
+			continue
+		}
+		if priority(ch.Kind) > priority(last.Kind) {
+			if last.StartLap < ch.StartLap {
+				last.EndLap = ch.StartLap - 1
+				out = append(out, ch)
+			} else {
+				*last = ch
+			}
+			continue
+		}
+		if ch.EndLap > last.EndLap {
+			ch.StartLap = last.EndLap + 1
+			if ch.StartLap <= ch.EndLap {
+				out = append(out, ch)
+			}
+		}
+	}
+	return out
+}
+
+func isFlag(kind string) bool {
+	return kind == KindSafetyCar || kind == KindVirtualSafetyCar || kind == KindRedFlag
+}
+
+func priority(kind string) int {
+	switch kind {
+	case KindStart, KindFinish:
+		return structuralPriority
+	case KindSafetyCar, KindVirtualSafetyCar, KindRedFlag:
+		return flagPriority
+	case KindPitPhase:
+		return pitPhasePriority
+	case KindDecisiveSwing:
+		return decisivePriority
+	default:
+		return 0
+	}
+}
+
+func messageLap(msg RaceControl, idx lapIndex) int {
+	if msg.LapNumber != nil && *msg.LapNumber > 0 {
+		return *msg.LapNumber
+	}
+	return idx.lapForTime(msg.Date)
+}
+
+func clampLap(lap, minLap, maxLap int) int {
+	if lap < minLap {
+		return minLap
+	}
+	if maxLap > 0 && lap > maxLap {
+		return maxLap
+	}
+	return lap
+}
+
+func parseTime(raw string) (time.Time, bool) {
+	if raw == "" {
+		return time.Time{}, false
+	}
+	at, err := time.Parse(time.RFC3339, raw)
+	if err != nil {
+		return time.Time{}, false
+	}
+	return at, true
+}
+
+func upperText(parts ...string) string {
+	return strings.ToUpper(strings.Join(parts, " "))
+}
+
+func firstNonEmpty(values ...string) string {
+	for _, value := range values {
+		if value != "" {
+			return value
+		}
+	}
+	return ""
+}
+
+func sortedDriverNumbers(drivers map[int]bool) []int {
+	out := make([]int, 0, len(drivers))
+	for driver := range drivers {
+		out = append(out, driver)
+	}
+	sort.Ints(out)
+	return out
+}
+
+func sliceToSet(values []int) map[int]bool {
+	out := make(map[int]bool, len(values))
+	for _, value := range values {
+		out[value] = true
+	}
+	return out
+}
+
+func minInt(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}

internal/chapters/chapters_test.go

@@ -0,0 +1,218 @@
+package chapters
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/AmanTahiliani/box-box/internal/models"
+)
+
+func TestDetectStructuralChapters(t *testing.T) {
+	chapters := Detect(nil, nil, testLaps(10, nil), 10)
+
+	if len(chapters) < 2 {
+		t.Fatalf("chapters len = %d, want at least start and finish", len(chapters))
+	}
+	if got := chapters[0]; got.Kind != KindStart || got.StartLap != 1 || got.EndLap != 1 {
+		t.Fatalf("start chapter = %+v, want L1-L1", got)
+	}
+	got := chapters[len(chapters)-1]
+	if got.Kind != KindFinish || got.StartLap != 9 || got.EndLap != 10 {
+		t.Fatalf("finish chapter = %+v, want L9-L10", got)
+	}
+}
+
+func TestDetectReturnsEmptyWithoutData(t *testing.T) {
+	if chapters := Detect(nil, nil, nil, 0); len(chapters) != 0 {
+		t.Fatalf("chapters = %+v, want empty", chapters)
+	}
+}
+
+func TestDetectFlagPeriods(t *testing.T) {
+	tests := []struct {
+		name      string
+		start     RaceControl
+		end       RaceControl
+		wantKind  string
+		wantTitle string
+	}{
+		{
+			name:      "safety car",
+			start:     rc(12, models.CategorySafetyCar, "", "SAFETY CAR DEPLOYED"),
+			end:       rc(15, models.CategorySafetyCar, "", "SAFETY CAR IN THIS LAP"),
+			wantKind:  KindSafetyCar,
+			wantTitle: "Safety Car (L12-L15)",
+		},
+		{
+			name:      "virtual safety car",
+			start:     rc(22, models.CategoryOther, "", "VSC DEPLOYED"),
+			end:       rc(24, models.CategoryOther, "", "VSC ENDING"),
+			wantKind:  KindVirtualSafetyCar,
+			wantTitle: "Virtual Safety Car (L22-L24)",
+		},
+		{
+			name:      "red flag",
+			start:     rc(31, models.CategoryFlag, models.FlagRed, "RED FLAG"),
+			end:       rc(33, models.CategoryFlag, models.FlagGreen, "GREEN FLAG"),
+			wantKind:  KindRedFlag,
+			wantTitle: "Red Flag (L31-L33)",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			chapters := Detect([]RaceControl{tt.start, tt.end}, nil, testLaps(40, nil), 40)
+			got := findKind(chapters, tt.wantKind)
+			if got == nil {
+				t.Fatalf("chapters = %+v, want %s", chapters, tt.wantKind)
+			}
+			if got.StartLap != rcLap(tt.start) || got.EndLap != rcLap(tt.end) || got.Title != tt.wantTitle {
+				t.Fatalf("flag chapter = %+v, want %s", *got, tt.wantTitle)
+			}
+		})
+	}
+}
+
+func TestDetectPitPhaseFromPitOutLapCluster(t *testing.T) {
+	pitOuts := map[int][]int{
+		5:  {1},
+		10: {2},
+		20: {3},
+		21: {4},
+		22: {5},
+		30: {6},
+		35: {7},
+		40: {8},
+		45: {9},
+		50: {10},
+	}
+	chapters := Detect(nil, nil, testLaps(55, pitOuts), 55)
+
+	got := findKind(chapters, KindPitPhase)
+	if got == nil {
+		t.Fatalf("chapters = %+v, want pit phase", chapters)
+	}
+	if got.StartLap != 20 || got.EndLap != 22 {
+		t.Fatalf("pit phase = %+v, want L20-L22", *got)
+	}
+	if len(got.DriverNumbers) != 3 || got.DriverNumbers[0] != 3 || got.DriverNumbers[2] != 5 {
+		t.Fatalf("pit phase drivers = %v, want [3 4 5]", got.DriverNumbers)
+	}
+}
+
+func TestDetectDecisiveSwingPersistsToFinish(t *testing.T) {
+	positions := []PositionSample{
+		pos(1, 1, 1),
+		pos(1, 16, 4),
+		pos(1, 55, 3),
+		pos(6, 16, 3),
+		pos(6, 55, 4),
+		pos(8, 44, 5),
+		pos(8, 63, 6),
+		pos(10, 44, 6),
+	}
+
+	chapters := Detect(nil, positions, testLaps(12, nil), 12)
+	got := findKind(chapters, KindDecisiveSwing)
+	if got == nil {
+		t.Fatalf("chapters = %+v, want decisive swing", chapters)
+	}
+	if got.StartLap != 6 || got.EndLap != 6 {
+		t.Fatalf("swing lap = %+v, want L6", *got)
+	}
+	if len(got.DriverNumbers) != 2 || got.DriverNumbers[0] != 16 || got.DriverNumbers[1] != 55 {
+		t.Fatalf("swing drivers = %v, want [16 55]", got.DriverNumbers)
+	}
+}
+
+func TestDetectFlagPeriodsWinOverConflictingChapters(t *testing.T) {
+	pitOuts := map[int][]int{
+		12: {1, 2},
+		13: {3, 4},
+		14: {5, 6},
+	}
+	rcs := []RaceControl{
+		rc(12, models.CategorySafetyCar, "", "SAFETY CAR DEPLOYED"),
+		rc(15, models.CategorySafetyCar, "", "SAFETY CAR IN THIS LAP"),
+	}
+
+	chapters := Detect(rcs, nil, testLaps(20, pitOuts), 20)
+	if got := findKind(chapters, KindSafetyCar); got == nil || got.StartLap != 12 || got.EndLap != 15 {
+		t.Fatalf("chapters = %+v, want safety car L12-L15", chapters)
+	}
+	if got := findKind(chapters, KindPitPhase); got != nil {
+		t.Fatalf("pit phase = %+v, want omitted under safety car", *got)
+	}
+	for i := 1; i < len(chapters); i++ {
+		if chapters[i].StartLap <= chapters[i-1].EndLap {
+			t.Fatalf("chapters overlap at %d: %+v then %+v", i, chapters[i-1], chapters[i])
+		}
+	}
+}
+
+func rcLap(r RaceControl) int {
+	if r.LapNumber == nil {
+		return 0
+	}
+	return *r.LapNumber
+}
+
+func findKind(chapters []Chapter, kind string) *Chapter {
+	for i := range chapters {
+		if chapters[i].Kind == kind {
+			return &chapters[i]
+		}
+	}
+	return nil
+}
+
+func testLaps(total int, pitOuts map[int][]int) []Lap {
+	var laps []Lap
+	for lap := 1; lap <= total; lap++ {
+		drivers := []int{1}
+		if pitDrivers := pitOuts[lap]; len(pitDrivers) > 0 {
+			drivers = pitDrivers
+		}
+		for _, driver := range drivers {
+			laps = append(laps, Lap{
+				DriverNumber: driver,
+				LapNumber:    lap,
+				DateStart:    lapTime(lap),
+				IsPitOutLap:  containsDriver(pitOuts[lap], driver),
+			})
+		}
+	}
+	return laps
+}
+
+func rc(lap int, category models.RaceControlCategory, flag models.Flag, message string) RaceControl {
+	return RaceControl{
+		Category:  category,
+		Flag:      flag,
+		Message:   message,
+		LapNumber: &lap,
+		Date:      lapTime(lap),
+	}
+}
+
+func pos(lap int, driver int, position int) PositionSample {
+	return PositionSample{
+		DriverNumber: driver,
+		Position:     position,
+		Date:         lapTime(lap),
+	}
+}
+
+func lapTime(lap int) string {
+	minute := lap - 1
+	return fmt.Sprintf("2025-05-25T13:%02d:00Z", minute)
+}
+
+func containsDriver(drivers []int, driver int) bool {
+	for _, candidate := range drivers {
+		if candidate == driver {
+			return true
+		}
+	}
+	return false
+}

internal/chapters/headlines.go

@@ -0,0 +1,233 @@
+package chapters
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/AmanTahiliani/box-box/internal/models"
+)
+
+// DriverIdentityInput carries session driver fields used for headline templates.
+type DriverIdentityInput struct {
+	DriverNumber int
+	NameAcronym  string
+	FullName     string
+	TeamName     string
+}
+
+type driverIdentity struct {
+	display string
+	team    string
+	acronym string
+}
+
+// BuildDriverMap indexes driver identity from session drivers and enriched results.
+func BuildDriverMap(drivers []models.Driver, results []DriverIdentityInput) map[int]driverIdentity {
+	out := map[int]driverIdentity{}
+	for _, d := range drivers {
+		if d.DriverNumber <= 0 {
+			continue
+		}
+		out[d.DriverNumber] = driverIdentity{
+			display: driverDisplayName(d.LastName, d.FullName, d.NameAcronym, d.BroadcastName),
+			team:    d.TeamName,
+			acronym: firstNonEmpty(d.NameAcronym, d.BroadcastName),
+		}
+	}
+	for _, r := range results {
+		if r.DriverNumber <= 0 {
+			continue
+		}
+		if _, ok := out[r.DriverNumber]; ok {
+			continue
+		}
+		out[r.DriverNumber] = driverIdentity{
+			display: driverDisplayName("", r.FullName, r.NameAcronym, ""),
+			team:    r.TeamName,
+			acronym: r.NameAcronym,
+		}
+	}
+	return out
+}
+
+// ApplyHeadlines fills Headline on each chapter using deterministic templates.
+func ApplyHeadlines(chapters []Chapter, drivers map[int]driverIdentity, rc []RaceControl, winnerNumber int) []Chapter {
+	out := make([]Chapter, len(chapters))
+	copy(out, chapters)
+	for i := range out {
+		out[i].Headline = headlineFor(out[i], drivers, rc, winnerNumber)
+	}
+	return out
+}
+
+func headlineFor(ch Chapter, drivers map[int]driverIdentity, rc []RaceControl, winnerNumber int) string {
+	switch ch.Kind {
+	case KindStart:
+		return pickVariant(ch.StartLap,
+			"Lights out — the field charges into Turn 1",
+			"Race start — Lap 1 shuffle at the front",
+		)
+	case KindSafetyCar:
+		if name := driverName(ch, drivers, incidentDriver(rc, ch.StartLap)); name != "" {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("%s incident brings out the Safety Car — leaders dive for the pits", name),
+				fmt.Sprintf("Safety Car deployed after %s stops on track", name),
+			)
+		}
+	case KindVirtualSafetyCar:
+		if name := driverName(ch, drivers, incidentDriver(rc, ch.StartLap)); name != "" {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("%s off track triggers the Virtual Safety Car", name),
+				fmt.Sprintf("Virtual Safety Car — %s loses control on Lap %d", name, ch.StartLap),
+			)
+		}
+		return pickVariant(ch.StartLap,
+			fmt.Sprintf("Virtual Safety Car deployed on Lap %d", ch.StartLap),
+			fmt.Sprintf("VSC period — field backs off on L%d–L%d", ch.StartLap, ch.EndLap),
+		)
+	case KindRedFlag:
+		if name := driverName(ch, drivers, incidentDriver(rc, ch.StartLap)); name != "" {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("%s crash forces a red flag on Lap %d", name, ch.StartLap),
+				fmt.Sprintf("Red flag after %s incident on Lap %d", name, ch.StartLap),
+			)
+		}
+		return pickVariant(ch.StartLap,
+			fmt.Sprintf("Red flag — session halted on Lap %d", ch.StartLap),
+			fmt.Sprintf("Race suspended under red flag on L%d–L%d", ch.StartLap, ch.EndLap),
+		)
+	case KindPitPhase:
+		names := driverNames(ch.DriverNumbers, drivers, 3)
+		if len(names) >= 2 {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("Mass pit-window scramble — %s and %s box on L%d–L%d", names[0], names[1], ch.StartLap, ch.EndLap),
+				fmt.Sprintf("Undercut window opens — %s leads the pit rush on L%d–L%d", names[0], ch.StartLap, ch.EndLap),
+			)
+		}
+		if len(names) == 1 {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("%s pits under green — strategy window opens on L%d", names[0], ch.StartLap),
+				fmt.Sprintf("Pit phase on L%d–L%d — %s among the first to stop", ch.StartLap, ch.EndLap, names[0]),
+			)
+		}
+	case KindDecisiveSwing:
+		if len(ch.DriverNumbers) >= 2 {
+			attacker := driverName(ch, drivers, ch.DriverNumbers[0])
+			defender := driverName(ch, drivers, ch.DriverNumbers[1])
+			pos := swingPosition(ch.Title)
+			if attacker != "" && defender != "" && pos > 0 {
+				return pickVariant(ch.StartLap,
+					fmt.Sprintf("%s overtakes %s for P%d", attacker, defender, pos),
+					fmt.Sprintf("%s charges past %s into P%d on Lap %d", attacker, defender, pos, ch.StartLap),
+				)
+			}
+		}
+		if len(ch.DriverNumbers) >= 1 {
+			attacker := driverName(ch, drivers, ch.DriverNumbers[0])
+			pos := swingPosition(ch.Title)
+			if attacker != "" && pos > 0 {
+				return pickVariant(ch.StartLap,
+					fmt.Sprintf("%s moves up to P%d on Lap %d", attacker, pos, ch.StartLap),
+					fmt.Sprintf("Decisive swing — %s climbs to P%d", attacker, pos),
+				)
+			}
+		}
+	case KindFinish:
+		winner := driverName(ch, drivers, winnerNumber)
+		if winner != "" {
+			return pickVariant(ch.StartLap,
+				fmt.Sprintf("%s crosses the line to take the win", winner),
+				fmt.Sprintf("Chequered flag — %s wins the race", winner),
+			)
+		}
+	}
+	return ch.Title
+}
+
+func pickVariant(seed int, variants ...string) string {
+	if len(variants) == 0 {
+		return ""
+	}
+	if seed < 0 {
+		seed = -seed
+	}
+	return variants[seed%len(variants)]
+}
+
+func driverName(_ Chapter, drivers map[int]driverIdentity, number int) string {
+	if number <= 0 {
+		return ""
+	}
+	if id, ok := drivers[number]; ok && id.display != "" {
+		return id.display
+	}
+	return ""
+}
+
+func driverNames(numbers []int, drivers map[int]driverIdentity, limit int) []string {
+	out := make([]string, 0, limit)
+	for _, number := range numbers {
+		if name := driverName(Chapter{}, drivers, number); name != "" {
+			out = append(out, name)
+			if len(out) >= limit {
+				break
+			}
+		}
+	}
+	return out
+}
+
+func driverDisplayName(lastName, fullName, acronym, broadcast string) string {
+	if lastName != "" {
+		return lastName
+	}
+	if fullName != "" {
+		parts := strings.Fields(fullName)
+		if len(parts) > 0 {
+			return parts[len(parts)-1]
+		}
+		return fullName
+	}
+	return firstNonEmpty(acronym, broadcast)
+}
+
+func incidentDriver(rc []RaceControl, startLap int) int {
+	for _, msg := range rc {
+		if msg.DriverNumber == nil || *msg.DriverNumber <= 0 {
+			continue
+		}
+		lap := 0
+		if msg.LapNumber != nil {
+			lap = *msg.LapNumber
+		}
+		if lap < startLap-1 || lap > startLap+1 {
+			continue
+		}
+		text := upperText(msg.Message, string(msg.Category))
+		if strings.Contains(text, "DEPLOY") ||
+			strings.Contains(text, "CLEAR") ||
+			strings.Contains(text, "ENDING") ||
+			strings.Contains(text, "GREEN") ||
+			strings.Contains(text, "CHEQUER") {
+			continue
+		}
+		return *msg.DriverNumber
+	}
+	return 0
+}
+
+func swingPosition(title string) int {
+	// Title format: "Decisive swing: #16 to P3 (L6)"
+	idx := strings.Index(title, "P")
+	if idx < 0 || idx+1 >= len(title) {
+		return 0
+	}
+	pos := 0
+	for i := idx + 1; i < len(title); i++ {
+		if title[i] < '0' || title[i] > '9' {
+			break
+		}
+		pos = pos*10 + int(title[i]-'0')
+	}
+	return pos
+}

internal/chapters/headlines_test.go

@@ -0,0 +1,199 @@
+package chapters
+
+import (
+	"testing"
+
+	"github.com/AmanTahiliani/box-box/internal/models"
+)
+
+func TestHeadlineStart(t *testing.T) {
+	ch := Chapter{Kind: KindStart, Title: "Start", StartLap: 1, EndLap: 1}
+	got := headlineFor(ch, nil, nil, 0)
+	want := "Race start — Lap 1 shuffle at the front"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineStartVariantByLap(t *testing.T) {
+	ch := Chapter{Kind: KindStart, Title: "Start", StartLap: 2, EndLap: 2}
+	got := headlineFor(ch, nil, nil, 0)
+	want := "Lights out — the field charges into Turn 1"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineSafetyCarWithDriver(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 55, NameAcronym: "SAI", FullName: "Carlos Sainz", TeamName: "Ferrari"},
+	})
+	rc := []RaceControl{
+		{
+			DriverNumber: intPtr(55),
+			LapNumber:    intPtr(12),
+			Message:      "CAR 55 STOPPED ON TRACK",
+		},
+		rc(12, models.CategorySafetyCar, "", "SAFETY CAR DEPLOYED"),
+		rc(15, models.CategorySafetyCar, "", "SAFETY CAR IN THIS LAP"),
+	}
+	ch := Chapter{
+		Kind:     KindSafetyCar,
+		Title:    "Safety Car (L12-L15)",
+		StartLap: 12,
+		EndLap:   15,
+	}
+	got := headlineFor(ch, drivers, rc, 0)
+	want := "Sainz incident brings out the Safety Car — leaders dive for the pits"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineSafetyCarFallbackWithoutDriver(t *testing.T) {
+	ch := Chapter{
+		Kind:     KindSafetyCar,
+		Title:    "Safety Car (L12-L15)",
+		StartLap: 12,
+		EndLap:   15,
+	}
+	got := headlineFor(ch, nil, nil, 0)
+	if got != ch.Title {
+		t.Fatalf("headline = %q, want fallback %q", got, ch.Title)
+	}
+}
+
+func TestHeadlineVirtualSafetyCar(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 16, NameAcronym: "LEC", FullName: "Charles Leclerc", TeamName: "Ferrari"},
+	})
+	rc := []RaceControl{
+		{
+			DriverNumber: intPtr(16),
+			LapNumber:    intPtr(22),
+			Message:      "CAR 16 OFF TRACK",
+		},
+		rc(22, models.CategoryOther, "", "VSC DEPLOYED"),
+		rc(24, models.CategoryOther, "", "VSC ENDING"),
+	}
+	ch := Chapter{
+		Kind:     KindVirtualSafetyCar,
+		Title:    "Virtual Safety Car (L22-L24)",
+		StartLap: 22,
+		EndLap:   24,
+	}
+	got := headlineFor(ch, drivers, rc, 0)
+	want := "Leclerc off track triggers the Virtual Safety Car"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineRedFlag(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 63, NameAcronym: "RUS", FullName: "George Russell", TeamName: "Mercedes"},
+	})
+	rc := []RaceControl{
+		{
+			DriverNumber: intPtr(63),
+			LapNumber:    intPtr(31),
+			Message:      "INCIDENT INVOLVING CAR 63",
+		},
+		rc(31, models.CategoryFlag, models.FlagRed, "RED FLAG"),
+		rc(33, models.CategoryFlag, models.FlagGreen, "GREEN FLAG"),
+	}
+	ch := Chapter{
+		Kind:     KindRedFlag,
+		Title:    "Red Flag (L31-L33)",
+		StartLap: 31,
+		EndLap:   33,
+	}
+	got := headlineFor(ch, drivers, rc, 0)
+	want := "Red flag after Russell incident on Lap 31"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlinePitPhase(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 1, NameAcronym: "VER", FullName: "Max Verstappen", TeamName: "Red Bull"},
+		{DriverNumber: 44, NameAcronym: "HAM", FullName: "Lewis Hamilton", TeamName: "Mercedes"},
+		{DriverNumber: 16, NameAcronym: "LEC", FullName: "Charles Leclerc", TeamName: "Ferrari"},
+	})
+	ch := Chapter{
+		Kind:          KindPitPhase,
+		Title:         "Pit phase (L20-L22)",
+		StartLap:      20,
+		EndLap:        22,
+		DriverNumbers: []int{1, 44, 16},
+	}
+	got := headlineFor(ch, drivers, nil, 0)
+	want := "Mass pit-window scramble — Verstappen and Hamilton box on L20–L22"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineDecisiveSwing(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 16, NameAcronym: "LEC", FullName: "Charles Leclerc", TeamName: "Ferrari"},
+		{DriverNumber: 55, NameAcronym: "SAI", FullName: "Carlos Sainz", TeamName: "Ferrari"},
+	})
+	ch := Chapter{
+		Kind:          KindDecisiveSwing,
+		Title:         "Decisive swing: #16 to P3 (L6)",
+		StartLap:      6,
+		EndLap:        6,
+		DriverNumbers: []int{16, 55},
+	}
+	got := headlineFor(ch, drivers, nil, 0)
+	want := "Leclerc overtakes Sainz for P3"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineFinish(t *testing.T) {
+	drivers := BuildDriverMap(nil, []DriverIdentityInput{
+		{DriverNumber: 1, NameAcronym: "VER", FullName: "Max Verstappen", TeamName: "Red Bull"},
+	})
+	ch := Chapter{
+		Kind:     KindFinish,
+		Title:    "Finish (L57-L58)",
+		StartLap: 57,
+		EndLap:   58,
+	}
+	got := headlineFor(ch, drivers, nil, 1)
+	want := "Chequered flag — Verstappen wins the race"
+	if got != want {
+		t.Fatalf("headline = %q, want %q", got, want)
+	}
+}
+
+func TestHeadlineFinishFallbackWithoutWinner(t *testing.T) {
+	ch := Chapter{
+		Kind:     KindFinish,
+		Title:    "Finish (L57-L58)",
+		StartLap: 57,
+		EndLap:   58,
+	}
+	got := headlineFor(ch, nil, nil, 0)
+	if got != ch.Title {
+		t.Fatalf("headline = %q, want fallback %q", got, ch.Title)
+	}
+}
+
+func TestApplyHeadlinesPreservesChapterFields(t *testing.T) {
+	input := []Chapter{
+		{Kind: KindStart, Title: "Start", StartLap: 1, EndLap: 1},
+	}
+	got := ApplyHeadlines(input, nil, nil, 0)
+	if len(got) != 1 || got[0].StartLap != 1 || got[0].Headline == "" {
+		t.Fatalf("ApplyHeadlines = %+v, want headline on start chapter", got)
+	}
+}
+
+func intPtr(v int) *int {
+	return &v
+}