/* Past Perfect — one stylesheet, no build step.
   Warm ivory ground, near-black text, one restrained accent. Artwork first:
   every rule here exists to keep the objects large and the interface quiet. */

:root {
  /* Ground and ink */
  --ivory:      #FBF6EC;
  --ivory-warm: #F5EDDF;
  --ivory-deep: #EFE5D3;
  --ink:        #17140F;
  --ink-2:      #453F33;
  --ink-3:      #6F675A;
  --line:       rgba(23, 20, 15, .14);
  --line-soft:  rgba(23, 20, 15, .07);

  /* The single accent, plus the one semantic colour a quiz cannot do without */
  --accent:     #A8432A;
  --accent-ink: #7E3320;
  --correct:    #3E6B4C;

  --shadow-card: 0 1px 2px rgba(23,20,15,.05), 0 12px 28px -18px rgba(23,20,15,.35);
  --shadow-lift: 0 2px 6px rgba(23,20,15,.07), 0 22px 44px -22px rgba(23,20,15,.42);

  /* Surfaces that have to know which way the light is coming from. Kept as
     tokens so the dark palette is a swap of values, not a second stylesheet. */
  --frame-sheen: radial-gradient(120% 80% at 50% 0%, rgba(255,255,255,.7), transparent 60%);
  --art-shadow:  0 1px 1px rgba(23,20,15,.10), 0 14px 30px -18px rgba(23,20,15,.55);
  --chip:        rgba(251,246,236,.92);
  --halo:        rgba(23,20,15,.07);
  --ivory-fade:  rgba(251,246,236,0);
  --on-accent:   #FBF6EC;
  --gold:        #8A6B24;
  --gold-soft:   #F1E6C8;
  --veil:        rgba(23, 20, 15, .95);

  --serif: Georgia, "Iowan Old Style", "Palatino Linotype", "Times New Roman", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  --canvas: 1240px;     /* gallery-like desktop canvas */
  --radius: 3px;        /* museum label, not app chrome */
  --reveal: 200ms;      /* the PRD's 150-250ms reveal window */
  --ease: cubic-bezier(.2, .7, .3, 1);

  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--ivory);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

img { max-width: 100%; display: block; }
[hidden] { display: none !important; }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

h1, h2, h3, .serif { font-family: var(--serif); font-weight: 400; letter-spacing: -.01em; }
h1 { font-size: clamp(2rem, 5.2vw, 3.4rem); line-height: 1.06; margin: 0 0 .5em; }
h2 { font-size: clamp(1.35rem, 2.6vw, 1.9rem); line-height: 1.2; margin: 0 0 .5em; }
h3 { font-size: 1.12rem; margin: 0 0 .35em; }
p  { margin: 0 0 1em; }

.wrap { width: 100%; max-width: var(--canvas); margin: 0 auto; padding: 0 clamp(16px, 4vw, 32px); }
.wrap-narrow { max-width: 680px; }
main { flex: 1 0 auto; }

/* ---------- Dark ----------
   Gallery Dark: a darkened exhibition room, where the object is the only bright
   thing on screen. The values below are declared twice on purpose -- once for a
   viewer whose system asks for dark and who has not chosen otherwise, and once
   for a viewer who picked dark explicitly. CSS has no way to share one block
   between a media query and an attribute selector, and duplicating values is
   cheaper than making dark mode depend on JavaScript. */

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --ivory:      #100F0D;
    --ivory-warm: #1A1917;
    --ivory-deep: #232120;
    --ink:        #F3EEE4;
    --ink-2:      #BDB5A6;
    --ink-3:      #8B8377;
    --line:       rgba(243, 238, 228, .16);
    --line-soft:  rgba(243, 238, 228, .08);

    --accent:     #D98A4E;
    --accent-ink: #E9A268;
    --correct:    #7FB08C;

    --shadow-card: 0 1px 2px rgba(0,0,0,.5), 0 18px 40px -20px rgba(0,0,0,.9);
    --shadow-lift: 0 2px 8px rgba(0,0,0,.55), 0 30px 60px -24px rgba(0,0,0,1);

    --frame-sheen: radial-gradient(78% 62% at 50% 42%, rgba(255,248,236,.085), transparent 72%);
    --art-shadow:  0 2px 4px rgba(0,0,0,.6), 0 26px 52px -20px rgba(0,0,0,.95);
    --chip:        rgba(16,15,13,.78);
    --halo:        rgba(243,238,228,.10);
    --ivory-fade:  rgba(16,15,13,0);
    --on-accent:   #14100C;
    --gold:        #E2BB66;
    --gold-soft:   #2C2618;
    --veil:        rgba(6, 6, 5, .96);

    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --ivory:      #100F0D;
  --ivory-warm: #1A1917;
  --ivory-deep: #232120;
  --ink:        #F3EEE4;
  --ink-2:      #BDB5A6;
  --ink-3:      #8B8377;
  --line:       rgba(243, 238, 228, .16);
  --line-soft:  rgba(243, 238, 228, .08);

  --accent:     #D98A4E;
  --accent-ink: #E9A268;
  --correct:    #7FB08C;

  --shadow-card: 0 1px 2px rgba(0,0,0,.5), 0 18px 40px -20px rgba(0,0,0,.9);
  --shadow-lift: 0 2px 8px rgba(0,0,0,.55), 0 30px 60px -24px rgba(0,0,0,1);

  --frame-sheen: radial-gradient(78% 62% at 50% 42%, rgba(255,248,236,.085), transparent 72%);
  --art-shadow:  0 2px 4px rgba(0,0,0,.6), 0 26px 52px -20px rgba(0,0,0,.95);
  --chip:        rgba(16,15,13,.78);
  --halo:        rgba(243,238,228,.10);
  --ivory-fade:  rgba(16,15,13,0);
  --on-accent:   #14100C;
  --gold:        #E2BB66;
  --gold-soft:   #2C2618;
  --veil:        rgba(6, 6, 5, .96);

  color-scheme: dark;
}

/* The one hover that flips which side of the accent the text sits on. */
.btn:hover { color: var(--on-accent); }
.btn-quiet:hover { color: var(--ink); }

/* ---------- Theme toggle ---------- */

.theme-toggle {
  display: inline-grid; place-items: center;
  width: 32px; height: 32px; margin-left: 4px; padding: 0;
  background: transparent; color: var(--ink-3); cursor: pointer;
  border: 1px solid transparent; border-radius: 50%;
  transition: color var(--reveal) var(--ease), border-color var(--reveal) var(--ease),
              background var(--reveal) var(--ease);
}
.theme-toggle:hover { color: var(--ink); border-color: var(--line-soft); background: var(--ivory-warm); }
.theme-toggle svg { width: 17px; height: 17px; display: block; }
.theme-toggle .icon-dark { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-light { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-dark { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-light { display: none; }
  :root:not([data-theme="light"]) .theme-toggle .icon-dark { display: block; }
}

/* ---------- Header / footer ---------- */

.site-head {
  display: flex; align-items: baseline; justify-content: space-between; gap: 10px 16px;
  flex-wrap: wrap;
  width: 100%; max-width: var(--canvas); margin: 0 auto;
  padding: clamp(14px, 2.4vw, 22px) clamp(16px, 4vw, 32px);
}
.wordmark {
  font-family: var(--serif); font-size: clamp(1.15rem, 2.4vw, 1.4rem);
  text-decoration: none; letter-spacing: -.015em; white-space: nowrap;
}
.wordmark-perfect { font-style: italic; color: var(--accent); }
.site-nav { display: flex; flex-wrap: wrap; align-items: center; gap: 6px clamp(12px, 2.2vw, 22px); font-size: .84rem; letter-spacing: .03em; }
.site-nav a { text-decoration: none; color: var(--ink-3); padding-bottom: 2px; border-bottom: 1px solid transparent; }
.site-nav a:hover { color: var(--ink); }
.site-nav a.is-active { color: var(--ink); border-bottom-color: var(--accent); }

.site-foot {
  margin-top: clamp(48px, 8vw, 96px);
  border-top: 1px solid var(--line-soft);
  padding: 28px clamp(16px, 4vw, 32px) 44px;
  width: 100%; max-width: var(--canvas); margin-inline: auto;
  font-size: .82rem; color: var(--ink-3);
}
.site-foot a { color: var(--ink-2); text-decoration-color: var(--line); text-underline-offset: 2px; }
.foot-links { display: flex; gap: 18px; flex-wrap: wrap; }
.foot-fine { max-width: 62ch; font-size: .76rem; color: var(--ink-3); opacity: .85; margin-bottom: 0; }

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5em;
  font: inherit; font-size: .95rem; letter-spacing: .01em;
  padding: 14px 26px; min-height: 48px;
  border: 1px solid var(--ink); border-radius: var(--radius);
  background: var(--ink); color: var(--ivory);
  text-decoration: none; cursor: pointer;
  transition: background var(--reveal) var(--ease), color var(--reveal) var(--ease),
              border-color var(--reveal) var(--ease), transform 120ms var(--ease);
}
.btn:hover { background: var(--accent); border-color: var(--accent); }
.btn:active { transform: translateY(1px); }
.btn-quiet { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-quiet:hover { background: var(--ivory-warm); color: var(--ink); border-color: var(--ink); }
.btn-lg { font-size: 1.05rem; padding: 17px 34px; min-height: 56px; }
.btn[disabled] { opacity: .45; pointer-events: none; }

.eyebrow {
  font-size: .72rem; letter-spacing: .16em; text-transform: uppercase;
  color: var(--ink-3); margin: 0 0 .9em;
}

/* ---------- Home ---------- */

.hero { padding: clamp(28px, 6vw, 72px) 0 clamp(24px, 4vw, 40px); }
.hero-lede { font-size: clamp(1.05rem, 2vw, 1.28rem); color: var(--ink-2); max-width: 34ch; margin-bottom: 1.6em; }
.hero-tagline { font-family: var(--serif); font-style: italic; color: var(--accent); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.hero-note { font-size: .82rem; color: var(--ink-3); margin: 1.4em 0 0; }

.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(24px, 5vw, 64px); align-items: center; }
.hero-strip { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; max-width: 460px; margin-left: auto; }
.hero-strip figure { margin: 0; background: var(--ivory-warm); border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden; aspect-ratio: 1; }
.hero-strip img { width: 100%; height: 100%; object-fit: cover; filter: saturate(.96); }
.hero-strip figure:nth-child(2) { transform: translateY(14px); }
.hero-strip figure:nth-child(3) { transform: translateY(-14px); }

.rule { border: 0; border-top: 1px solid var(--line-soft); margin: clamp(36px, 6vw, 64px) 0; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: clamp(14px, 2vw, 22px); }
.card {
  background: var(--ivory-warm); border: 1px solid var(--line-soft);
  border-radius: var(--radius); padding: 22px 22px 24px; text-decoration: none;
  transition: transform var(--reveal) var(--ease), box-shadow var(--reveal) var(--ease);
  display: block;
}
a.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-card); }
.card p:last-child { margin-bottom: 0; }
.card-meta { font-size: .8rem; color: var(--ink-3); }

/* ---------- The board ---------- */

.game { padding-bottom: clamp(24px, 5vw, 40px); }

.game-bar {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 4px 0 clamp(12px, 2vw, 20px); flex-wrap: wrap;
}
.game-title { font-family: var(--serif); font-size: 1.05rem; margin: 0; }
.game-title small { font-family: var(--sans); font-size: .78rem; color: var(--ink-3); letter-spacing: .04em; }

.pips { display: flex; gap: 6px; align-items: center; }
.pip { width: 9px; height: 9px; border-radius: 50%; border: 1px solid var(--line); background: transparent; transition: background var(--reveal) var(--ease), border-color var(--reveal) var(--ease); }
.pip.is-current { border-color: var(--ink); box-shadow: 0 0 0 3px var(--halo); }
.pip.is-hit { background: var(--correct); border-color: var(--correct); }
.pip.is-miss { background: var(--accent); border-color: var(--accent); }

.question {
  font-family: var(--serif); font-size: clamp(1.25rem, 2.8vw, 1.75rem);
  text-align: center; margin: 0 0 clamp(14px, 2.2vw, 22px);
}
.question em { font-style: italic; color: var(--accent); }

.board { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(10px, 1.8vw, 24px); align-items: stretch; }

/* The card is a wrapper so the zoom control can sit *beside* the choice button
   rather than inside it. A button inside a button is invalid markup, and the
   reason this control exists is that looking closer used to mean answering. */
.choice-card { position: relative; display: flex; min-width: 0; }

.choice {
  position: relative; display: flex; flex-direction: column; flex: 1;
  background: var(--ivory-warm); border: 1px solid var(--line-soft);
  border-radius: var(--radius); padding: 0; margin: 0; cursor: pointer;
  font: inherit; color: inherit; text-align: left; overflow: hidden; min-width: 0;
  transition: box-shadow var(--reveal) var(--ease), border-color var(--reveal) var(--ease),
              transform var(--reveal) var(--ease);
}
.choice:hover:not(.is-locked) { box-shadow: var(--shadow-lift); transform: translateY(-2px); }
.choice.is-locked { cursor: default; }

/* Sized from the viewport, not from a guess: the board, its labels, the reveal
   and the Next button all have to fit a laptop without scrolling. */
.choice-frame {
  height: clamp(170px, calc(100dvh - 430px), 460px);
  display: grid;
  grid-template-rows: minmax(0, 1fr);
  grid-template-columns: minmax(0, 1fr);
  place-items: center;
  min-width: 0;
  padding: clamp(10px, 1.6vw, 20px);
  background: var(--frame-sheen), var(--ivory-warm);
}
.choice-frame img {
  max-width: 100%; max-height: 100%; width: auto; height: auto;
  object-fit: contain;
  box-shadow: var(--art-shadow);
  opacity: 0; transition: opacity 260ms var(--ease);
}
.choice-frame img.is-ready { opacity: 1; }

/* Once the labels arrive the picture gives up some room, so the reveal line and
   the Next button stay on screen without a scroll. */
.choice.is-revealed .choice-frame { height: clamp(150px, calc(100dvh - 570px), 380px); }

.choice-key {
  position: absolute; top: 10px; left: 10px; z-index: 2;
  width: 26px; height: 26px; display: grid; place-items: center;
  border: 1px solid var(--line); border-radius: 50%;
  background: var(--chip); font-size: .72rem; letter-spacing: .04em; color: var(--ink-2);
}

/* What the thing is, and whose it is -- shown before the answer, because you
   cannot read a picture without knowing whether it is a painting or a
   photograph of one. What it never says is when. */
.choice-kind {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: 2px 10px;
  padding: 10px clamp(12px, 1.6vw, 18px);
  border-top: 1px solid var(--line-soft);
}
.kind-form { font-family: var(--serif); font-weight: 400; font-size: 1rem; line-height: 1.25; }
.kind-museum {
  font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3);
}

.zoom-btn {
  position: absolute; top: 10px; right: 10px; z-index: 3;
  display: inline-flex; align-items: center; gap: 6px;
  min-height: 34px; padding: 6px 12px 6px 10px; margin: 0;
  font: inherit; font-size: .74rem; letter-spacing: .05em;
  border: 1px solid var(--line); border-radius: 999px;
  background: var(--chip); color: var(--ink-2); cursor: pointer;
  transition: color var(--reveal) var(--ease), border-color var(--reveal) var(--ease);
}
.zoom-btn svg { width: 16px; height: 16px; display: block; }
.zoom-btn { touch-action: manipulation; }
.zoom-btn:hover { color: var(--ink); border-color: var(--ink); }

/* Nothing that dates the object is disclosed until an answer is given. */
.choice-label {
  border-top: 1px solid var(--line-soft);
  padding: 0 clamp(12px, 1.6vw, 18px);
  max-height: 0; opacity: 0; overflow: hidden;
  transition: max-height 240ms var(--ease), opacity 200ms var(--ease), padding 240ms var(--ease);
}
.choice.is-revealed .choice-label { max-height: 260px; opacity: 1; padding: 14px clamp(12px, 1.6vw, 18px) 16px; }
.choice-year { font-family: var(--serif); font-size: 1.5rem; line-height: 1.1; }
.choice-date { font-size: .78rem; color: var(--ink-3); margin: 2px 0 8px; }
.choice-title { font-family: var(--serif); font-size: 1rem; line-height: 1.3; margin: 0 0 2px; }
.choice-artist { font-size: .82rem; color: var(--ink-2); margin: 0 0 6px; }
.choice-credit { font-size: .72rem; color: var(--ink-3); line-height: 1.45; }
.choice-credit a { color: var(--ink-3); }
.choice-museum { color: var(--ink-2); }

.choice.is-earlier { border-color: var(--correct); box-shadow: inset 0 0 0 1px var(--correct); }
.choice.is-chosen-wrong { border-color: var(--accent); box-shadow: inset 0 0 0 1px var(--accent); }
.choice-verdict {
  position: absolute; top: 10px; left: 44px; z-index: 2;
  font-size: .68rem; letter-spacing: .12em; text-transform: uppercase;
  padding: 5px 9px; border-radius: 999px; background: var(--ink); color: var(--ivory);
  opacity: 0; transform: translateY(-4px); transition: opacity var(--reveal) var(--ease), transform var(--reveal) var(--ease);
}
.choice.is-revealed .choice-verdict { opacity: 1; transform: none; }
.choice.is-earlier .choice-verdict { background: var(--correct); }

/* ---------- Reveal ---------- */

.reveal {
  margin-top: clamp(14px, 2vw, 22px);
  border-top: 1px solid var(--line);
  padding-top: clamp(14px, 2vw, 20px);
  display: grid; grid-template-columns: 1fr auto; gap: 16px; align-items: center;
  opacity: 0; transform: translateY(6px);
  transition: opacity var(--reveal) var(--ease), transform var(--reveal) var(--ease);
}
.reveal[hidden] { display: none; }
.reveal.is-shown { opacity: 1; transform: none; }
.reveal-verdict { font-family: var(--serif); font-size: 1.2rem; margin: 0 0 2px; }
.reveal-verdict.is-hit { color: var(--correct); }
.reveal-verdict.is-miss { color: var(--accent); }
.reveal-insight { margin: 0; color: var(--ink-2); max-width: 62ch; }
.reveal-gap { font-size: .82rem; color: var(--ink-3); margin: 4px 0 0; }

/* Challenging a friend is a second thought, never a rival to Next: it sits in
   the reveal's spare column, quiet, and says what it did underneath itself. */
.reveal-aside { display: flex; flex-direction: column; align-items: flex-end; gap: 6px; }
.challenge-note { font-size: .74rem; color: var(--ink-3); margin: 0; max-width: 30ch; text-align: right; }
.review-challenge { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 14px; }
.review-challenge .challenge-note { text-align: left; }
.challenge-onward { text-align: center; padding-top: 6px; }

/* Sticky, not static. On a laptop the reveal pushes Next below the fold, and
   having to scroll before you can continue was the worst thing about the
   board. Sticky costs nothing on a page that already fits. */
.game-foot {
  position: sticky; bottom: 0; z-index: 15;
  margin-top: 18px; display: flex; justify-content: space-between;
  align-items: center; gap: 14px; flex-wrap: wrap;
}
.game-foot:has(#next:not([hidden])) {
  padding: 12px 0 calc(12px + env(safe-area-inset-bottom));
  background: linear-gradient(to top, var(--ivory) 72%, var(--ivory-fade));
}
.hint { font-size: .78rem; color: var(--ink-3); }
.hint kbd {
  font: inherit; font-size: .72rem; border: 1px solid var(--line); border-bottom-width: 2px;
  border-radius: 3px; padding: 1px 6px; background: var(--ivory-warm);
}

/* ---------- Results ---------- */

.results { max-width: 720px; margin: 0 auto; text-align: center; padding: clamp(20px, 5vw, 48px) 0; }
.score-line { font-family: var(--serif); font-size: clamp(2.6rem, 9vw, 4.4rem); line-height: 1; margin: 0; }
.score-line span { color: var(--ink-3); font-size: .45em; }
.score-caption { font-family: var(--serif); font-style: italic; font-size: 1.15rem; color: var(--accent); margin: .35em 0 .9em; }

/* The number, said out loud. "8/10" means nothing on its own; "better than 74%
   of today's players" is the thing somebody repeats. */
.score-standing { font-size: 1.02rem; color: var(--ink-2); margin: 0 0 1.6em; }

/* The one fact worth taking away from a round. */
.learned {
  border: 1px solid var(--line); border-left: 3px solid var(--accent);
  border-radius: var(--radius); background: var(--ivory-warm);
  padding: 20px clamp(18px, 3vw, 28px); margin: 0 0 26px; text-align: left;
}
/* The pair behind the fact, framed the way the review detail frames its own:
   the older thing first, an arrow, then the newer. The first figure is always
   the earlier one, so it carries the same green the review strip uses. */
.learned-pair {
  display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: start; gap: clamp(8px, 2vw, 18px); margin: 0 0 16px;
}
.learned-obj { margin: 0; min-width: 0; }
.learned-frame {
  display: grid; grid-template-rows: minmax(0, 1fr); grid-template-columns: minmax(0, 1fr);
  place-items: center; overflow: hidden;
  height: clamp(96px, 16vh, 150px); padding: 8px;
  background: var(--ivory); border: 1px solid var(--line-soft); border-radius: var(--radius);
}
.learned-frame img { max-width: 100%; max-height: 100%; width: auto; height: auto; object-fit: contain; box-shadow: var(--art-shadow); }
.learned-obj:first-child .learned-frame { border-color: var(--correct); }
.learned-obj figcaption { display: block; padding-top: 8px; }
.learned-flag {
  display: block; margin-bottom: 2px;
  font-size: .64rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3);
}
.learned-obj:first-child .learned-flag { color: var(--correct); }
.learned-year { display: block; font-family: var(--serif); font-size: 1.05rem; }
.learned-obj figcaption b { display: block; font-family: var(--serif); font-weight: 400; font-size: .88rem; line-height: 1.3; color: var(--ink-2); }
.learned-vs { align-self: center; font-size: 1.1rem; color: var(--ink-3); }
.learned-line { font-family: var(--serif); font-size: clamp(1.05rem, 2.4vw, 1.3rem); line-height: 1.4; margin: 0 0 .4em; }
.learned-note { font-size: .84rem; color: var(--ink-3); margin: 0; }

.result-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line-soft); border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden; margin-bottom: 34px; }
.result-cell { background: var(--ivory); padding: 16px 10px; }
.result-cell b { display: block; font-family: var(--serif); font-size: 1.7rem; font-weight: 400; line-height: 1.1; }
.result-cell span { font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }

/* ---------- The ten, reviewable ----------
   A row of green squares says how you did and nothing else. These are the same
   ten results, but each one opens the pair it stands for. */

.review-title { font-size: 1.1rem; margin: 34px 0 .2em; text-align: left; }
.review-hint { font-size: .8rem; color: var(--ink-3); text-align: left; margin: 0 0 14px; }

.review-strip { display: grid; grid-template-columns: repeat(10, minmax(0, 1fr)); gap: 6px; }
.review-tile {
  position: relative; display: grid; place-items: center; gap: 0;
  aspect-ratio: 1; padding: 0; margin: 0; cursor: pointer;
  font: inherit; border: 1px solid var(--line-soft); border-radius: var(--radius);
  background: var(--ivory-deep); color: var(--ink-3);
  transition: transform 120ms var(--ease), box-shadow var(--reveal) var(--ease);
}
.review-tile:hover { transform: translateY(-2px); box-shadow: var(--shadow-card); }
.review-tile.is-hit { background: var(--correct); border-color: var(--correct); color: var(--on-accent); }
.review-tile.is-miss { background: var(--ivory-deep); border-color: var(--line); color: var(--accent); }
.review-tile.is-open { box-shadow: 0 0 0 2px var(--accent); }
.review-n { position: absolute; top: 4px; left: 6px; font-size: .62rem; opacity: .75; }
.review-mark { font-size: 1.05rem; line-height: 1; }

.review-detail {
  margin-top: 14px; text-align: left;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--ivory-warm); padding: clamp(14px, 2.4vw, 22px);
}
.review-head { font-size: .84rem; color: var(--ink-3); margin: 0 0 14px; }
.review-pair { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(10px, 2vw, 20px); }
.review-obj { margin: 0; position: relative; }
.review-frame {
  display: grid; grid-template-rows: minmax(0, 1fr); grid-template-columns: minmax(0, 1fr);
  place-items: center; overflow: hidden;
  height: clamp(120px, 22vh, 200px); padding: 10px;
  background: var(--ivory); border: 1px solid var(--line-soft); border-radius: var(--radius);
}
.review-frame img { max-width: 100%; max-height: 100%; width: auto; height: auto; object-fit: contain; box-shadow: var(--art-shadow); }
.review-obj.is-earlier .review-frame { border-color: var(--correct); }
.review-flag {
  display: inline-block; margin-bottom: 6px;
  font-size: .64rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3);
}
.review-obj.is-earlier .review-flag { color: var(--correct); }
.review-obj.is-picked .review-flag { font-weight: 700; }
.review-obj figcaption { display: block; padding-top: 8px; }
.review-obj .review-year { display: block; font-family: var(--serif); font-size: 1.15rem; }
.review-obj figcaption b { display: block; font-family: var(--serif); font-weight: 400; font-size: .95rem; line-height: 1.3; }
.review-meta { display: block; font-size: .74rem; color: var(--ink-3); margin-top: 2px; }
.review-link { display: inline-block; font-size: .72rem; color: var(--ink-3); margin-top: 5px; }
.review-insight { margin: 14px 0 0; font-size: .9rem; color: var(--ink-2); }

/* ---------- The share card ---------- */

.share-preview {
  border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; background: var(--ivory-warm); margin: 0 auto 18px;
  /* The card is 9:16, so at full column width it would be a metre tall on a
     desktop. Shown at phone size; it is shared at 1080x1920. */
  max-width: 270px;
}
.share-preview canvas { display: block; width: 100%; height: auto; }
.results-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }
.results-onward { margin-top: 30px; padding-top: 24px; border-top: 1px solid var(--line-soft); }
.share-note { font-size: .78rem; color: var(--ink-3); margin-top: 14px; min-height: 1.2em; }

/* ---------- Museums ---------- */

.museum-head { display: grid; grid-template-columns: 1fr; gap: 8px; padding: clamp(20px, 4vw, 40px) 0 clamp(16px, 3vw, 28px); }
.museum-flag { display: inline-block; width: 34px; height: 3px; background: var(--accent); margin-bottom: 14px; }
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 1px; background: var(--line-soft); border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden; margin: 24px 0 32px; }
.fact { background: var(--ivory); padding: 16px 18px; }
.fact b { display: block; font-family: var(--serif); font-size: 1.5rem; font-weight: 400; line-height: 1.2; }
.fact span { font-size: .74rem; letter-spacing: .07em; text-transform: uppercase; color: var(--ink-3); }

.gallery { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: clamp(10px, 1.6vw, 18px); }
.gallery figure { margin: 0; }
.gallery-frame {
  background: var(--ivory-warm); border: 1px solid var(--line-soft);
  border-radius: var(--radius); aspect-ratio: 1; overflow: hidden; padding: 10px;
  display: grid; grid-template-rows: minmax(0, 1fr); grid-template-columns: minmax(0, 1fr);
  place-items: center;
}
.gallery-frame img { max-width: 100%; max-height: 100%; width: auto; height: auto; object-fit: contain; }
.gallery figcaption { font-size: .76rem; color: var(--ink-3); margin-top: 8px; line-height: 1.4; }
.gallery figcaption b {
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
  font-family: var(--serif); font-weight: 400; font-size: .92rem; color: var(--ink); margin-bottom: 2px;
}

/* ---------- Prose ---------- */

.prose { max-width: 68ch; padding: clamp(20px, 4vw, 44px) 0; }

/* A prose block on a page that also carries full-canvas sections. It keeps the
   reading measure, but the block itself stays canvas-wide, so its heading lines
   up with the grid below it instead of floating in from the left -- and it
   keeps the .wrap gutter, which the .prose padding shorthand would otherwise
   drop. */
.prose-flush { max-width: var(--canvas); padding-inline: clamp(16px, 4vw, 32px); }
.prose-flush > * { max-width: 68ch; }
.prose h2 { margin-top: 1.8em; }
.prose ul { padding-left: 1.1em; }
.prose li { margin-bottom: .5em; }
.prose table { width: 100%; border-collapse: collapse; font-size: .9rem; margin: 1.2em 0; }
.prose th, .prose td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--line-soft); vertical-align: top; }
.prose th { font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); font-weight: 400; }
.prose code { font-size: .88em; background: var(--ivory-deep); padding: 1px 5px; border-radius: 2px; }

.callout { background: var(--ivory-warm); border-left: 2px solid var(--accent); padding: 16px 20px; margin: 1.5em 0; }
.callout p:last-child { margin-bottom: 0; }

/* Short trailing links that read as one gesture rather than a sentence. Below
   the narrowest phones the nowrap comes off, so the line wraps instead of
   pushing the paragraph sideways. */
.link-whole { white-space: nowrap; }
@media (max-width: 400px) { .link-whole { white-space: normal; } }

/* ---------- Stats ---------- */

.stats-h { margin: clamp(34px, 5vw, 52px) 0 .3em; }
.stats-h small { font-family: var(--sans); font-size: .74rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3); margin-left: 10px; }
.section-lede { font-size: .92rem; color: var(--ink-2); max-width: 62ch; margin: 0 0 18px; }
.stats-reset { margin-top: 42px; }

/* A progress bar that several different things share. */
.meter { height: 4px; border-radius: 999px; background: var(--ivory-deep); overflow: hidden; margin: 10px 0 6px; }
.meter span { display: block; height: 100%; background: var(--accent); border-radius: 999px; transition: width var(--reveal) var(--ease); }

/* ---------- Art Eye ---------- */

/* A number and a sentence, so it takes a sentence's width rather than the
   canvas's: at 1240px the card was mostly empty warm paper. The measure matches
   .prose, which is what the body of it is. */
.eye-card {
  display: grid; grid-template-columns: auto 1fr; gap: clamp(16px, 3vw, 28px); align-items: center;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--ivory-warm); padding: clamp(18px, 3vw, 26px);
  max-width: 68ch;
}
.eye-score { text-align: center; }
.eye-score b { display: block; font-family: var(--serif); font-weight: 400; font-size: clamp(2.4rem, 7vw, 3.4rem); line-height: 1; }
.eye-score span { font-size: .74rem; letter-spacing: .1em; text-transform: uppercase; color: var(--accent); }
.eye-body p { margin: 0 0 .4em; }
.eye-body p:last-child { margin: 0; }

/* ---------- Museum passport ----------
   A passport page per collection: a rank stamped in the corner, and the
   distance to the next one under it. */

.passport { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 14px; }
.stamp {
  position: relative; overflow: hidden;
  border: 1px solid var(--line-soft); border-radius: var(--radius);
  background: var(--ivory-warm); padding: 20px 20px 18px;
}
.stamp.is-earned { border-color: var(--line); }
.stamp h3 { margin: 0 0 1px; padding-right: 84px; font-size: 1.05rem; }
.stamp-city { font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3); margin: 0 0 12px; }
.stamp-count { font-family: var(--serif); font-size: 1.1rem; margin: 0; }
.stamp-next { font-size: .76rem; color: var(--ink-3); margin: 0; }

/* The stamp itself: a rubber-stamp roundel, tilted, and faded out until the
   rank behind it has actually been earned. */
.stamp-mark {
  position: absolute; top: 14px; right: 12px; width: 72px; height: 72px;
  display: grid; place-items: center; text-align: center;
  border: 2px solid var(--ink-3); border-radius: 50%;
  color: var(--ink-3); opacity: .28; transform: rotate(-11deg);
  transition: opacity var(--reveal) var(--ease), color var(--reveal) var(--ease),
              border-color var(--reveal) var(--ease);
}
.stamp-mark::before {
  content: ""; position: absolute; inset: 4px; border: 1px solid currentColor; border-radius: 50%;
}
.stamp-mark span { font-size: .6rem; letter-spacing: .1em; text-transform: uppercase; padding: 0 4px; }
.stamp.is-earned .stamp-mark { opacity: 1; color: var(--accent); border-color: var(--accent); }

/* ---------- Achievements ----------
   Grouped, because a flat list of six boxes is a list, not a cabinet. Locked
   ones stay readable: they are the reason to keep playing. */

.ach-group { margin-bottom: clamp(24px, 4vw, 38px); }
.ach-head { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.ach-head h3 { margin: 0; font-size: 1.05rem; }
.ach-head p { margin: 0; font-size: .82rem; color: var(--ink-3); flex: 1; }
.ach-tally { font-size: .72rem; letter-spacing: .1em; color: var(--ink-3); border: 1px solid var(--line); border-radius: 999px; padding: 3px 10px; }

.ach-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 12px; }
.ach {
  position: relative; display: grid; grid-template-columns: auto 1fr; gap: 14px; align-items: start;
  border: 1px solid var(--line-soft); border-radius: var(--radius);
  background: var(--ivory-warm); padding: 16px 16px 15px;
  transition: border-color var(--reveal) var(--ease), box-shadow var(--reveal) var(--ease);
}
.ach.is-earned { border-color: var(--gold); box-shadow: var(--shadow-card); }
.ach-badge {
  display: grid; place-items: center; width: 46px; height: 46px; border-radius: 50%;
  background: var(--ivory-deep); color: var(--ink-3);
  transition: background var(--reveal) var(--ease), color var(--reveal) var(--ease);
}
.ach.is-earned .ach-badge { background: var(--gold-soft); color: var(--gold); }
.ach-icon { width: 24px; height: 24px; display: block; }
.ach-body h3 { margin: 1px 0 2px; font-size: 1rem; }
.ach-body p { margin: 0; font-size: .8rem; color: var(--ink-3); line-height: 1.45; }
.ach.is-earned .ach-body p { color: var(--ink-2); }
.ach-progress { font-size: .7rem; letter-spacing: .06em; color: var(--ink-3); margin: 0; }
.ach-share { margin-top: 10px; }
.ach-tick {
  position: absolute; top: 12px; right: 14px;
  font-size: .8rem; color: var(--gold);
}
.ach:not(.is-earned) { opacity: .82; }

/* ---------- Finishing scores ----------
   Formerly "score distribution", which is a phrase from a statistics lecture.
   One sentence of explanation, then ten labelled bars. */

.score-chart { display: grid; gap: 4px; max-width: 520px; }
.score-row { display: grid; grid-template-columns: 3.4em 1fr 7.4em; align-items: center; gap: 12px; font-size: .84rem; }
.score-key { font-family: var(--serif); font-size: 1rem; text-align: right; color: var(--ink-2); }
.score-key small { font-size: .68rem; color: var(--ink-3); }
.score-track { height: 18px; background: var(--ivory-deep); border-radius: 2px; overflow: hidden; }
.score-fill { display: block; height: 100%; background: var(--ink-2); border-radius: 2px; transition: width var(--reveal) var(--ease); }
.score-count { font-size: .74rem; color: var(--ink-3); }
.score-row.is-usual .score-fill { background: var(--accent); }
.score-row.is-usual .score-key { color: var(--ink); }
.score-row.is-latest .score-track { box-shadow: 0 0 0 1px var(--accent); }
.score-row.is-latest .score-count { color: var(--accent); }

.reminder {
  display: none; align-items: center; justify-content: space-between; gap: 14px; flex-wrap: wrap;
  border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 18px; margin-top: 26px;
  background: var(--ivory-warm);
}
.reminder.is-shown { display: flex; }
.reminder p { margin: 0; font-size: .88rem; }

.empty { color: var(--ink-3); font-style: italic; max-width: 62ch; }
.loading { display: grid; place-items: center; min-height: 40vh; color: var(--ink-3); font-family: var(--serif); font-style: italic; }

/* ---------- Pick a game ----------
   The per-collection games used to live behind a tab called "Museums", which
   reads as reference material. This grid puts every way to play on one screen. */

.play-section { margin: clamp(28px, 5vw, 56px) 0; }
.play-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: clamp(12px, 1.6vw, 18px); }
.play-card {
  display: flex; flex-direction: column;
  border: 1px solid var(--line-soft); border-radius: var(--radius);
  background: var(--ivory-warm); padding: 20px 20px 18px;
  transition: box-shadow var(--reveal) var(--ease), border-color var(--reveal) var(--ease);
}
.play-card:hover { box-shadow: var(--shadow-card); border-color: var(--line); }
.play-card.is-feature { border-color: var(--accent); }
.play-card h3 { margin: 0 0 4px; font-size: 1.2rem; }
.play-kicker { font-size: .68rem; letter-spacing: .12em; text-transform: uppercase; color: var(--ink-3); margin: 0 0 8px; }
.play-card.is-feature .play-kicker { color: var(--accent); }
.play-count { font-size: .84rem; color: var(--ink-2); margin: 0 0 16px; flex: 1; }
.play-actions { display: flex; flex-wrap: wrap; gap: 8px; }
.play-more { display: inline-block; margin-top: 14px; font-size: .74rem; color: var(--ink-3); text-decoration-color: var(--line); }
.play-more:hover { color: var(--ink); }
.btn-sm { font-size: .84rem; padding: 9px 16px; min-height: 40px; }

/* ---------- The lightbox ----------
   Zoom is its own room. Nothing in here can answer the question. */

.lightbox {
  position: fixed; inset: 0; z-index: 60;
  display: grid; grid-template-rows: minmax(0, 1fr) auto;
  background: var(--veil);
}
.lightbox[hidden] { display: none !important; }
body.is-zoomed { overflow: hidden; }
html:has(body.is-zoomed) { overflow: hidden; }

.lightbox-stage {
  position: relative; overflow: hidden; display: grid; place-items: center;
  padding: clamp(12px, 3vw, 40px); touch-action: none; cursor: zoom-in;
}
.lightbox-stage.is-magnified { cursor: grab; }
.lightbox-stage.is-magnified:active { cursor: grabbing; }
#lightbox-img {
  max-width: 100%; max-height: 100%; width: auto; height: auto; object-fit: contain;
  transform-origin: center center; will-change: transform;
  transition: transform 120ms var(--ease);
  user-select: none; -webkit-user-drag: none;
}
.lightbox-stage.is-magnified #lightbox-img { transition: none; }
#lightbox-img.is-swapping { animation: swap-in 200ms var(--ease); }
@keyframes swap-in { from { opacity: .25; } to { opacity: 1; } }

.lightbox-bar {
  display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  padding: 14px clamp(14px, 4vw, 32px) calc(14px + env(safe-area-inset-bottom));
  background: var(--ivory); border-top: 1px solid var(--line-soft);
}
.lightbox-caption { margin: 0; font-size: .88rem; color: var(--ink-2); max-width: 62ch; }
.lightbox-caption b { font-family: var(--serif); font-weight: 400; font-size: 1.02rem; }
.lightbox-note { display: block; font-size: .74rem; color: var(--ink-3); }
.lightbox-tools { display: flex; align-items: center; gap: 8px; }
.lightbox-btn {
  font: inherit; font-size: 1rem; min-width: 40px; min-height: 40px; padding: 0 12px;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--ivory-warm); color: var(--ink); cursor: pointer;
}
.lightbox-btn:hover { border-color: var(--ink); }
.lightbox-done { font-size: .88rem; padding: 0 18px; background: var(--ink); color: var(--ivory); border-color: var(--ink); }
.lightbox-done:hover { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.lightbox-level { font-size: .76rem; color: var(--ink-3); min-width: 3.6em; text-align: center; }

/* Which of the two you are looking at, and that there is a second one at all --
   the swipe is only obvious once you know something is there to swipe to. */
.lightbox-which { display: inline-flex; align-items: center; gap: 6px; padding: 0 2px; }
.lightbox-dot {
  width: 7px; height: 7px; border-radius: 50%;
  border: 1px solid var(--line); background: transparent;
  transition: background var(--reveal) var(--ease), border-color var(--reveal) var(--ease);
}
.lightbox-dot.is-on { background: var(--ink); border-color: var(--ink); }
.lightbox-gap { width: 8px; }

/* ---------- Responsive ---------- */

@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-strip { grid-template-columns: repeat(4, 1fr); gap: 8px; max-width: none; margin-left: 0; }
  .hero-strip figure:nth-child(2), .hero-strip figure:nth-child(3) { transform: none; }
  .reveal { grid-template-columns: 1fr; }
  .reveal-aside { align-items: flex-start; }
  .challenge-note { text-align: left; }
}

@media (max-width: 860px) {
  /* Stacked, the measure has nothing left to do: it only reads as a card that
     failed to line up with the band above and the passport below. */
  .eye-card { grid-template-columns: 1fr; text-align: center; max-width: none; }
  .review-pair { grid-template-columns: 1fr; }
}

@media (max-width: 700px) {
  /* Stacked cards, and a Next button that stays under the thumb -- which the
     sticky footer already does, on every width. */
  .board { grid-template-columns: minmax(0, 1fr); gap: 10px; }
  .choice-frame { height: clamp(130px, calc((100dvh - 380px) / 2), 300px); }
  .choice.is-revealed .choice-frame { height: clamp(100px, calc((100dvh - 520px) / 2), 220px); }
  .game-foot { justify-content: stretch; }
  .game-foot .btn { flex: 1; }
  .hint { display: none; }
  /* Beside a card that answers the question, this control has to be missable in
     one direction only: a thumb aiming here must not land on the picture. */
  .zoom-btn span { display: none; }
  .zoom-btn {
    top: 8px; right: 8px;
    padding: 0; min-width: 48px; min-height: 48px; justify-content: center;
    background: var(--chip); box-shadow: var(--shadow-lift);
  }
  .zoom-btn svg { width: 22px; height: 22px; }
  .lightbox-gap { width: 4px; }
  .site-nav { font-size: .78rem; gap: 12px; }
  .result-grid { grid-template-columns: 1fr 1fr; }
  .review-strip { grid-template-columns: repeat(5, minmax(0, 1fr)); }
  .learned-pair { gap: 8px; }
  .learned-frame { height: clamp(84px, 13vh, 120px); padding: 6px; }
  .learned-year { font-size: .95rem; }
  .learned-obj figcaption b { font-size: .8rem; }
  .lightbox-bar { flex-direction: column; align-items: stretch; }
  .lightbox-tools { justify-content: flex-end; }
}

@media (max-width: 430px) {
  .site-head { flex-direction: column; align-items: flex-start; gap: 6px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: 1ms !important; animation-duration: 1ms !important; }
}

@media print { .site-nav, .game-foot, .btn, .zoom-btn, .lightbox { display: none; } }