#361

frontend/src/lib/gekanator.ts

@@ -30,7 +30,7 @@ export type GekanatorQuestionSource =
     | 'ai_generated'
     | 'admin_curated'
 
-export type GekanatorPerformanceMode = 'normal'
+export type GekanatorPerformanceMode = 'lite' | 'normal'
 
 export type GekanatorQuestionCondition =
     | { type: 'tag'; key: string }

frontend/src/pages/GekanatorPage.tsx

@@ -29,6 +29,7 @@ import type { FC } from 'react'
 import type { GekanatorAnswerLog,
 	      GekanatorAnswerValue,
 	      GekanatorExtraQuestion,
+	      GekanatorPerformanceMode,
 	      GekanatorQuestionCondition,
 	      GekanatorQuestionKind,
 	      GekanatorQuestion,
@@ -161,6 +162,7 @@ const confidenceTemperature = 6
 const gameStorageKey = 'gekanator:game:v1'
 const recentGamesStorageKey = 'gekanator:recent-games:v1'
 const backgroundMotionStorageKey = 'gekanator:background-motion:v1'
+const performanceModeStorageKey = 'gekanator:performance-mode:v1'
 const maxQuestionSuggestionsPerGame = 3
 const maxStoredRecentGames = 12
 const mascotAssetByState: Record<MascotState, string> = {
@@ -389,8 +391,14 @@ const storeRecentGameSummary = (
 }
 
 
-const loadBackgroundMotionMode = (): BackgroundMotionMode => {
+const loadBackgroundMotionMode = (
-  const fallbackMode = 'on'
+    performanceMode?:  GekanatorPerformanceMode,
+): BackgroundMotionMode => {
+  const fallbackMode =
+      performanceMode === 'lite' ? 'off'
+      : performanceMode === 'normal' ? 'on'
+      : detectDefaultPerformanceMode () === 'lite' ? 'off'
+      : 'on'
   try
   {
     const raw = localStorage.getItem (backgroundMotionStorageKey)
@@ -406,6 +414,38 @@ const loadBackgroundMotionMode = (): BackgroundMotionMode => {
 }
 
 
+const detectDefaultPerformanceMode = (): GekanatorPerformanceMode => {
+  if (typeof window === 'undefined')
+    return 'normal'
+
+  const isMobileWidth =
+      typeof window.matchMedia === 'function'
+	? window.matchMedia ('(max-width: 767px)').matches
+	: window.innerWidth <= 767
+  const memory = (navigator as Navigator & { deviceMemory?: number }).deviceMemory
+  if ((typeof memory === 'number' && memory <= 4) || isMobileWidth)
+    return 'lite'
+
+  return 'normal'
+}
+
+
+const loadPerformanceMode = (): GekanatorPerformanceMode => {
+  try
+  {
+    const raw = localStorage.getItem (performanceModeStorageKey)
+    if (raw === 'lite' || raw === 'normal')
+      return raw
+  }
+  catch
+  {
+    return detectDefaultPerformanceMode ()
+  }
+
+  return detectDefaultPerformanceMode ()
+}
+
+
 const resettableExtraQuestionState = (): {
     extraQuestions:        GekanatorExtraQuestion[]
     extraQuestionAnswers:  Record<string, GekanatorAnswerValue>
@@ -1015,9 +1055,11 @@ const rankedEntriesForCounts = <T extends string | number> (
 const buildQuestionsForCandidateIds = (
     { candidateIds,
       materialIndex,
+      performanceMode,
       acceptedQuestions }: { candidateIds:      number[]
-				     materialIndex:     GekanatorQuestionMaterialIndex
+			     materialIndex:     GekanatorQuestionMaterialIndex
-				     acceptedQuestions: GekanatorQuestion[] },
+			     performanceMode:   GekanatorPerformanceMode
+			     acceptedQuestions: GekanatorQuestion[] },
 ): GekanatorQuestion[] => {
   const total = candidateIds.length
   if (total === 0)
@@ -1047,16 +1089,23 @@ const buildQuestionsForCandidateIds = (
     const monthDay = materialIndex.originalMonthDayByPostId.get (postId)
     if (monthDay)
       monthDayCounts.set (monthDay, (monthDayCounts.get (monthDay) ?? 0) + 1)
-    materialIndex.titleTermsByPostId.get (postId)?.forEach (term =>
+    if (performanceMode === 'normal')
-	titleTermCounts.set (term, (titleTermCounts.get (term) ?? 0) + 1))
+      materialIndex.titleTermsByPostId.get (postId)?.forEach (term =>
+	  titleTermCounts.set (term, (titleTermCounts.get (term) ?? 0) + 1))
     const titleLength = materialIndex.titleLengthByPostId.get (postId) ?? 0
     titleLengths.push (titleLength)
     if (materialIndex.titleAsciiPostIds.has (postId))
       ++asciiCount
   })
 
-  const tagCap = total >= 120 ? 128 : 96
+  const tagCap =
-  const titleTermCap = total >= 80 ? 10 : total >= 24 ? 14 : 20
+      performanceMode === 'lite'
+	? total >= 80 ? 96 : 64
+	: total >= 120 ? 128 : 96
+  const titleTermCap =
+      performanceMode === 'lite'
+	? 0
+	: total >= 80 ? 10 : total >= 24 ? 14 : 20
   const factCap = total >= 80 ? 8 : 12
   const sortedLengths = [...titleLengths].sort ((a, b) => a - b)
   const titleLengthMedian = sortedLengths[Math.floor (sortedLengths.length / 2)] ?? 0
@@ -1132,16 +1181,17 @@ const buildQuestionsForCandidateIds = (
 	    materialIndex }))
       })
 
-  rankedEntriesForCounts ({ counts: titleTermCounts, total, cap: titleTermCap })
+  if (performanceMode === 'normal')
-      .filter (([term]) => String (term).length <= 24)
+    rankedEntriesForCounts ({ counts: titleTermCounts, total, cap: titleTermCap })
-      .forEach (([term]) => {
+	.filter (([term]) => String (term).length <= 24)
-	questions.push (buildIndexedQuestion ({
+	.forEach (([term]) => {
-	    condition: { type: 'title-contains', text: String (term) },
+	  questions.push (buildIndexedQuestion ({
-	    text: `題名に「${ term }」が含まれる?`,
+	      condition: { type: 'title-contains', text: String (term) },
-	    kind: 'title',
+	      text: `題名に「${ term }」が含まれる?`,
-	    priorityWeight: .96,
+	      kind: 'title',
-	    materialIndex }))
+	      priorityWeight: .96,
-      })
+	      materialIndex }))
+	})
 
   return mergeQuestions ([...questions, ...acceptedQuestions])
 }
@@ -1565,33 +1615,41 @@ const contradictionPenaltyFor = ({
 }
 
 
-const chooseQuestion = (
+const chooseQuestion = ({
-    { posts,
+    posts,
-      questions,
+    questions,
-      scores,
+    scores,
-      answers,
+    answers,
-      askedIds,
+    askedIds,
-      gameSeed,
+    gameSeed,
-      recentFirstQuestionPenaltyById,
+    recentFirstQuestionPenaltyById,
-      userPriorWeights,
+    userPriorWeights,
-      materialIndex,
+    performanceMode,
-      matchIndex }: { posts:      Post[]
+    materialIndex,
-		      questions:  GekanatorQuestion[]
+    matchIndex,
-		      scores:     Map<number, number>
+}: {
-		      answers:    GekanatorAnswerLog[]
+    posts:      Post[]
-		      askedIds:   Set<string>
+    questions:  GekanatorQuestion[]
-		      gameSeed:   string
+    scores:     Map<number, number>
-		      recentFirstQuestionPenaltyById: Map<string, number>
+    answers:    GekanatorAnswerLog[]
-		      userPriorWeights: Map<number, number>
+    askedIds:   Set<string>
-		      materialIndex: GekanatorQuestionMaterialIndex
+    gameSeed:   string
-		      matchIndex: GekanatorMatchIndex },
+    recentFirstQuestionPenaltyById: Map<string, number>
-): GekanatorQuestion | null => {
+    userPriorWeights: Map<number, number>
+    performanceMode: GekanatorPerformanceMode
+    materialIndex: GekanatorQuestionMaterialIndex
+    matchIndex: GekanatorMatchIndex
+}): GekanatorQuestion | null => {
+  const candidateIds = posts.map (post => post.id)
+  const candidateIdSet = new Set (candidateIds)
   const dynamicMatchIndex = new Map<string, Set<number>> ()
 
   const invertedSignature = (signature: string): string =>
       signature.replace (/[01]/g, value => value === '1' ? '0' : '1')
 
-  const redundantSignatures = (candidates:  Post[]): Set<string> => {
+  const redundantSignatures = (
+      candidates:  Post[],
+  ): Set<string> => {
     const signatures = new Set<string> ()
     questions
 	.filter (question => askedIds.has (question.id))
@@ -1610,6 +1668,89 @@ const chooseQuestion = (
     return signatures
   }
 
+  if (performanceMode === 'lite')
+    {
+      const nonTagCount =
+	  questions.filter (question => askedIds.has (question.id) && question.kind !== 'tag').length
+      const ranked = questions
+	  .filter (question => !(askedIds.has (question.id)))
+	  .map (question => {
+	    if (isQuestionHardFilteredAfterAnswers (question, answers))
+	      return null
+
+	    const yes = matchingPostCountInIds ({
+		candidateIds,
+		candidateIdSet,
+		posts,
+		materialIndex,
+		matchIndex,
+		question,
+		dynamicMatchIndex })
+	    const no = posts.length - yes
+	    if (yes === 0 || no === 0)
+	      return null
+
+	    const splitScore = Math.abs (posts.length / 2 - yes) / posts.length
+	    const minSide = posts.length < 10 ? 1 : Math.max (2, Math.floor (posts.length * .08))
+	    const narrowPenalty = yes < minSide || no < minSide ? .18 : 0
+	    const tagPenalty = question.kind === 'tag' && nonTagCount < 3 ? .1 : 0
+	    const contradictionPenalty = contradictionPenaltyFor ({ question, answers })
+	    const sourceBonus = sourcePriorityOffset (question)
+	    const priorityBonus = priorityWeightOffset (question)
+	    const categoryPenalty = questionCategoryPenalty (question, answers.length, 0)
+
+	    return {
+		question,
+		score: splitScore * 100
+		    + narrowPenalty
+		    + tagPenalty
+		    + contradictionPenalty
+		    + sourceBonus
+		    + priorityBonus
+		    + categoryPenalty,
+		narrow: narrowPenalty > 0 }
+	  })
+	  .filter ((item): item is {
+	      question:  GekanatorQuestion
+	      score:     number
+	      narrow:    boolean } => item !== null && Number.isFinite (item.score))
+	  .sort ((a, b) => {
+	    if (a.score !== b.score)
+	      return a.score - b.score
+
+	    return a.question.id.localeCompare (b.question.id)
+	  })
+      const pool = (
+	  ranked.some (item => !(item.narrow))
+	    ? ranked.filter (item => !(item.narrow))
+	    : ranked)
+	  .slice (0, 8)
+
+      if (pool.length === 0)
+	return null
+
+      const bestScore = pool[0]?.score ?? 0
+      const weightedPool = pool.map (item => ({
+	  ...item,
+	  weight: Math.exp ((bestScore - item.score) / 1.6) }))
+      const totalPoolWeight =
+	  weightedPool.reduce ((sum, item) => sum + item.weight, 0) || 1
+      const seed = `${ gameSeed }:lite:${ [...askedIds].sort ().join ('|') }:${
+	  weightedPool.map (item => `${ item.question.id }:${ item.score.toFixed (4) }`).join ('|')
+      }`
+      const target = deterministicUnitFloat (seed) * totalPoolWeight
+      let cumulative = 0
+
+      for (const item of weightedPool)
+	{
+	  cumulative += item.weight
+	  if (target <= cumulative)
+	    return item.question
+	}
+
+      return weightedPool[weightedPool.length - 1]?.question ?? null
+    }
+
   const scoredPosts = posts
       .map (post => ({ post, score: scores.get (post.id) ?? 0 }))
       .sort ((a, b) => b.score - a.score)
@@ -2220,6 +2361,7 @@ const nextQuestionPlanFor = (
       gameSeed,
       recentFirstQuestionPenaltyById,
       userPriorWeights,
+      performanceMode,
       materialIndex,
       matchIndex,
       lastGuessQuestionCount,
@@ -2234,6 +2376,7 @@ const nextQuestionPlanFor = (
     				      gameSeed:   string
     				      recentFirstQuestionPenaltyById: Map<string, number>
     				      userPriorWeights: Map<number, number>
+    				      performanceMode: GekanatorPerformanceMode
     				      materialIndex: GekanatorQuestionMaterialIndex
     				      matchIndex: GekanatorMatchIndex
     				      lastGuessQuestionCount: number
@@ -2296,6 +2439,7 @@ const nextQuestionPlanFor = (
       buildQuestionsForCandidateIds ({
 	  candidateIds: scopePosts.map (post => post.id),
 	  materialIndex,
+	  performanceMode,
 	  acceptedQuestions })
 
   if (eligiblePosts.length === 1)
@@ -2361,6 +2505,7 @@ const nextQuestionPlanFor = (
       gameSeed,
       recentFirstQuestionPenaltyById,
       userPriorWeights,
+      performanceMode,
       materialIndex,
       matchIndex })
 
@@ -2963,8 +3108,10 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
   const canPersistGame = user !== null
   const [recentGames, setRecentGames] = useState<RecentGameSummary[]> (
       () => loadRecentGames ())
+  const [performanceMode] =
+      useState<GekanatorPerformanceMode> (() => loadPerformanceMode ())
   const [backgroundMotionMode, setBackgroundMotionMode] = useState<BackgroundMotionMode> (
-      () => loadBackgroundMotionMode ())
+      () => loadBackgroundMotionMode (loadPerformanceMode ()))
   const [prefersReducedMotion, setPrefersReducedMotion] = useState (false)
   const [gameSeed, setGameSeed] = useState (
       storedGame?.gameSeed ?? createGameSeed ())
@@ -3181,6 +3328,17 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
     }
   }, [backgroundMotionMode])
 
+  useEffect (() => {
+    try
+    {
+      localStorage.setItem (performanceModeStorageKey, performanceMode)
+    }
+    catch
+    {
+      return
+    }
+  }, [performanceMode])
+
   const askedQuestionById = useMemo (
       () => new Map (askedQuestionBank.map (question => [question.id, question])),
       [askedQuestionBank])
@@ -3203,6 +3361,9 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
       () => new Map (scoringQuestions.map (question => [question.id, question])),
       [scoringQuestions])
   const recentFirstQuestionPenaltyById = useMemo (() => {
+    if (performanceMode === 'lite')
+      return new Map<string, number> ()
+
     const penalties = new Map<string, number> ()
 
     recentGames.forEach ((game, index) => {
@@ -3215,10 +3376,12 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
     })
 
     return penalties
-  }, [recentGames])
+  }, [performanceMode, recentGames])
   const userPriorWeights = useMemo (
-      () => userPriorWeightsFor (posts, recentGames),
+      () => performanceMode === 'lite'
-      [posts, recentGames])
+	  ? new Map<number, number> ()
+	  : userPriorWeightsFor (posts, recentGames),
+      [performanceMode, posts, recentGames])
   const availablePosts = useMemo (
       () => posts.filter (post => !(rejectedPostIds.has (post.id))),
       [posts, rejectedPostIds])
@@ -3234,6 +3397,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	  gameSeed,
 	  recentFirstQuestionPenaltyById,
 	  userPriorWeights,
+	  performanceMode,
 	  materialIndex,
 	  matchIndex: acceptedQuestionMatchIndex,
 	  lastGuessQuestionCount,
@@ -3241,7 +3405,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	  winningRunStartAnswerCount }),
       [posts, eligiblePosts, availablePosts, acceptedQuestions, scores,
 	  answers, askedIds, gameSeed, recentFirstQuestionPenaltyById,
-	  userPriorWeights, materialIndex, acceptedQuestionMatchIndex,
+	  userPriorWeights, performanceMode, materialIndex, acceptedQuestionMatchIndex,
 	  lastGuessQuestionCount, winningRunTargetId, winningRunStartAnswerCount])
   const winningRunTargetPost = useMemo (
       () => questionPlan.winningRunTargetId === null
@@ -3294,28 +3458,35 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
   const reviewCorrectPost =
       posts.find (post => post.id === reviewCorrectPostId) ?? null
   const effectiveResultWon =
-      resultWon
+      resultWon ?? (
-      ?? ((reviewGuessedPostId !== null && reviewCorrectPostId !== null)
+	  reviewGuessedPostId !== null
-	  ? reviewGuessedPostId === reviewCorrectPostId
+	  && reviewCorrectPostId !== null
-	  : null)
+	    ? reviewGuessedPostId === reviewCorrectPostId
+	    : null)
   const effectiveBackgroundMotionMode =
-      backgroundMotionMode === 'off'
+      performanceMode === 'lite'
-      ? 'off'
+	? 'off'
-      : (prefersReducedMotion
+	: backgroundMotionMode === 'off'
-	 ? 'calm'
+	? 'off'
-	 : backgroundMotionMode)
+	: prefersReducedMotion
+	  ? 'calm'
+	  : backgroundMotionMode
   const backgroundPosts = useMemo (
-      () => backgroundPostsFor ({
+      () => performanceMode === 'lite'
+	  ? []
+	  : backgroundPostsFor ({
 	      phase,
 	      eligiblePosts,
 	      availablePosts,
 	      displayedGuess,
 	      reviewCorrectPost,
 	      reviewGuessedPost }),
-      [phase, eligiblePosts, availablePosts, displayedGuess, reviewCorrectPost,
+      [performanceMode, phase, eligiblePosts, availablePosts, displayedGuess,
-	  reviewGuessedPost])
+	  reviewCorrectPost, reviewGuessedPost])
   const backgroundVisualSeed =
-	`${ gameSeed }:${ phase }:${ answers.length }:${ activeGuessId ?? '' }:${
+      performanceMode === 'lite'
+	? ''
+	: `${ gameSeed }:${ phase }:${ answers.length }:${ activeGuessId ?? '' }:${
 	    questionPlan.question?.id ?? ''
 	}:${ questionPlan.questionMode ?? '' }:${ winningRunQuestionsAsked }:${
 	    rejectedPostIds.size
@@ -3446,6 +3617,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
     let recoveredQuestions = buildQuestionsForCandidateIds ({
 	candidateIds: recoveredEligiblePosts.map (post => post.id),
 	materialIndex,
+	performanceMode,
 	acceptedQuestions })
     let recoveredScoringQuestions = mergeQuestions ([
 	...recoveredQuestions,
@@ -3471,6 +3643,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
       recoveredQuestions = buildQuestionsForCandidateIds ({
 	  candidateIds: recoveredEligiblePosts.map (post => post.id),
 	  materialIndex,
+	  performanceMode,
 	  acceptedQuestions })
       recoveredScoringQuestions = mergeQuestions ([
 	  ...recoveredQuestions,
@@ -3494,6 +3667,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	  gameSeed,
 	  recentFirstQuestionPenaltyById,
 	  userPriorWeights,
+	  performanceMode,
 	  materialIndex,
 	  matchIndex: acceptedQuestionMatchIndex })
       const fallbackQuestion = nextQuestion ?? chooseFallbackQuestion ({
@@ -3561,6 +3735,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
   }, [
       posts,
       gameSeed,
+      performanceMode,
       materialIndex,
       acceptedQuestions,
       acceptedQuestionMatchIndex,
@@ -3631,6 +3806,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	gameSeed,
 	recentFirstQuestionPenaltyById,
 	userPriorWeights,
+	performanceMode,
 	materialIndex,
 	matchIndex: acceptedQuestionMatchIndex,
 	lastGuessQuestionCount,
@@ -3664,6 +3840,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	    gameSeed,
 	    recentFirstQuestionPenaltyById,
 	    userPriorWeights,
+	    performanceMode,
 	    materialIndex,
 	    matchIndex: acceptedQuestionMatchIndex,
 	    lastGuessQuestionCount,
@@ -3894,6 +4071,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	gameSeed,
 	recentFirstQuestionPenaltyById,
 	userPriorWeights,
+	performanceMode,
 	materialIndex,
 	matchIndex: acceptedQuestionMatchIndex,
 	lastGuessQuestionCount,
@@ -4108,15 +4286,16 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	  <title>{`グカネータ | ${ SITE_TITLE }`}</title>
 	</Helmet>
 
-	<GekanatorBackdrop
+	{performanceMode !== 'lite' && (
-	    posts={backgroundPosts}
+	    <GekanatorBackdrop
-	    mascotAsset={mascotAsset}
+		posts={backgroundPosts}
-	    phase={phase}
+		mascotAsset={mascotAsset}
-	    displayedGuess={displayedGuess}
+		phase={phase}
-	    visualSeed={backgroundVisualSeed}
+		displayedGuess={displayedGuess}
-	    motionMode={effectiveBackgroundMotionMode}
+		visualSeed={backgroundVisualSeed}
-	    winningRunTargetPost={winningRunActive ? winningRunTargetPost : null}
+		motionMode={effectiveBackgroundMotionMode}
-	    winningRunQuestionCount={winningRunQuestionsAsked}/>
+		winningRunTargetPost={winningRunActive ? winningRunTargetPost : null}
+		winningRunQuestionCount={winningRunQuestionsAsked}/>)}
 
 	<div className="relative z-10 mx-auto max-w-4xl space-y-6">
 	  <header className="flex flex-wrap items-end justify-between gap-3">
@@ -4126,31 +4305,32 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 	      </h1>
 	    </div>
 	    <div className="flex flex-wrap justify-end gap-2">
-	      <div className="rounded-full border border-yellow-300 bg-white/80 px-2 py-1
+	      {performanceMode === 'normal' && (
-			      text-xs shadow-sm backdrop-blur dark:border-red-800
+		  <div className="rounded-full border border-yellow-300 bg-white/80 px-2 py-1
-			      dark:bg-red-950/75">
+				  text-xs shadow-sm backdrop-blur dark:border-red-800
-		<span className="mr-2 font-bold text-neutral-600 dark:text-neutral-300">
+				  dark:bg-red-950/75">
-		  背景
+		    <span className="mr-2 font-bold text-neutral-600 dark:text-neutral-300">
-		</span>
+		      背景
-		{[{ mode: 'off' as const, label: 'オフ' },
+		    </span>
-		  { mode: 'on' as const, label: 'オン' }]
+		    {[{ mode: 'off' as const, label: 'オフ' },
-		 .map (({ mode, label }) => (
+		      { mode: 'on' as const, label: 'オン' }]
-		    <button
+		     .map (({ mode, label }) => (
-			key={mode}
+			<button
-			type="button"
+			    key={mode}
-			className={cn (
+			    type="button"
-			    'rounded-full px-2.5 py-1 transition-colors',
+			    className={cn (
-			    backgroundMotionMode === mode
+				'rounded-full px-2.5 py-1 transition-colors',
-			      ? 'bg-pink-600 text-white'
+				backgroundMotionMode === mode
-			      : 'text-neutral-600 hover:bg-yellow-100 dark:text-neutral-300 dark:hover:bg-red-900')}
+				  ? 'bg-pink-600 text-white'
-			onClick={() => setBackgroundMotionMode (mode)}>
+				  : 'text-neutral-600 hover:bg-yellow-100 dark:text-neutral-300 dark:hover:bg-red-900')}
-		      {label}
+			    onClick={() => setBackgroundMotionMode (mode)}>
-		    </button>))}
+			  {label}
-		{prefersReducedMotion && effectiveBackgroundMotionMode !== 'off' && (
+			</button>))}
-		    <span className="ml-2 text-[11px] text-neutral-500 dark:text-neutral-400">
+		    {prefersReducedMotion && effectiveBackgroundMotionMode !== 'off' && (
-		      端末設定により控えめ表示
+			<span className="ml-2 text-[11px] text-neutral-500 dark:text-neutral-400">
-		    </span>)}
+			  端末設定により控えめ表示
-	      </div>
+			</span>)}
+		  </div>)}
 	    </div>
 	  </header>
 
@@ -4428,7 +4608,7 @@ const GekanatorPage: FC<{ user: User | null }> = ({ user }) => {
 
 		      {reviewGuessedPostId !== null && reviewCorrectPostId !== null && (
 			  <p className="text-sm text-neutral-600 dark:text-neutral-300">
-			    判定: {reviewGuessedPostId === reviewCorrectPostId ? '当たり' : 'はずれ'}
+			    判定: {reviewGuessedPostId === reviewCorrectPostId ? '当たり' : '違ひ'}
 			  </p>)}
 
 		      {saveMutation.isError && (