:root {
  --bg: #f5efe3;
  --bg-deep: #ebe3d3;
  --card: #fffdf8;
  --ink: #1c1d21;
  --ink-soft: #55575f;
  --ink-faint: #8a8b92;
  --line: #d8cfbd;
  --code-bg: #f3eee4;
  --ok: #1f8a4c;
  --miss: #c8331b;
  --accent: #d9480f;
  --time: #2f6fdf;
  --text: #8a45d6;
  --numbers: #dd6a1f;
  --names: #208a5c;
  --places: #0f8a98;
  --money: #b98a00;
  --web: #d43f78;
  --tok-keyword: #a1287a;
  --tok-string: #1f7a4a;
  --tok-number: #b04a0a;
  --tok-comment: #8a8b92;
  --tok-method: #2459b8;
  --shadow: 6px 6px 0 var(--ink);
  --serif: 'Iowan Old Style', 'Palatino Linotype', Palatino, 'Book Antiqua', Georgia, serif;
  --sans: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --mono: ui-monospace, 'SF Mono', SFMono-Regular, Menlo, Consolas, monospace;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme='light']) {
    --bg: #15171c;
    --bg-deep: #101216;
    --card: #20232b;
    --ink: #ece8df;
    --ink-soft: #b4b2ac;
    --ink-faint: #85848a;
    --line: #353944;
    --code-bg: #181a20;
    --ok: #4cc27f;
    --miss: #ff7059;
    --accent: #ff8a4c;
    --tok-keyword: #e28ac8;
    --tok-string: #7fd3a0;
    --tok-number: #ffb07a;
    --tok-comment: #7d7f88;
    --tok-method: #8ab4ff;
    --shadow: 6px 6px 0 #000;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

html { background: var(--bg); }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 var(--sans);
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-underline-offset: 3px; }

button { font: inherit; color: inherit; cursor: pointer; }

:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

/* ---- header and footer ---- */

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 20px 24px 8px;
}

.wordmark {
  font: 600 26px/1 var(--serif);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.wordmark em { color: var(--accent); }

.nav { display: flex; gap: 4px; flex-wrap: wrap; }

.nav a {
  padding: 6px 12px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  color: var(--ink-soft);
}

.nav a:hover { color: var(--ink); background: var(--bg-deep); }
.nav a[aria-current='page'] { color: var(--bg); background: var(--ink); }

main {
  flex: 1;
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 16px 24px 48px;
  outline: none;
}

.foot {
  max-width: 1040px;
  margin: 0 auto;
  padding: 24px;
  color: var(--ink-faint);
  font-size: 14px;
  text-align: center;
}

/* ---- the round ---- */

.play { max-width: 640px; margin: 0 auto; }

.meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin: 8px 0 22px;
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 15px;
}

.pips { display: flex; gap: 6px; margin: 0; padding: 0; list-style: none; }

.pips li {
  width: 22px;
  height: 8px;
  border-radius: 4px;
  background: var(--line);
}

.pips li.ok { background: var(--ok); }
.pips li.miss { background: var(--miss); }
.pips li.now { background: var(--ink); }

.stage { position: relative; perspective: 1400px; }

.stage::before,
.stage::after {
  content: '';
  position: absolute;
  inset: 10px 6px -6px;
  border: 2px solid var(--ink);
  border-radius: 20px;
  background: var(--card);
  z-index: 0;
}

.stage::before { transform: rotate(-2.4deg); opacity: 0.55; }
.stage::after { transform: rotate(1.6deg); opacity: 0.8; }

.card {
  --cat: var(--accent);
  position: relative;
  z-index: 1;
  min-height: 380px;
  padding: 28px 32px 30px;
  border: 2px solid var(--ink);
  border-radius: 20px;
  background: var(--card);
  box-shadow: var(--shadow);
  overflow: hidden;
  transform-origin: center;
  touch-action: pan-y;
}

.card[data-cat='time'] { --cat: var(--time); }
.card[data-cat='text'] { --cat: var(--text); }
.card[data-cat='numbers'] { --cat: var(--numbers); }
.card[data-cat='names'] { --cat: var(--names); }
.card[data-cat='places'] { --cat: var(--places); }
.card[data-cat='money'] { --cat: var(--money); }
.card[data-cat='web'] { --cat: var(--web); }

.card::before {
  content: '';
  position: absolute;
  inset: 0 0 auto;
  height: 8px;
  background: var(--cat);
}

.chip {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--cat);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.front {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 24px;
}

.claim {
  margin: 0;
  font: 500 clamp(28px, 6vw, 42px)/1.18 var(--serif);
  letter-spacing: -0.01em;
  text-wrap: balance;
}

.claim code, .truth code {
  font-family: var(--mono);
  font-size: 0.8em;
}

.watermark {
  position: absolute;
  right: 18px;
  bottom: -18px;
  font: italic 700 150px/1 var(--serif);
  color: var(--cat);
  opacity: 0.08;
  pointer-events: none;
  user-select: none;
}

.card-foot {
  display: flex;
  justify-content: space-between;
  color: var(--ink-faint);
  font-size: 14px;
  font-weight: 600;
}

.drag-label {
  position: absolute;
  top: 26px;
  right: 26px;
  padding: 4px 12px;
  border: 3px solid currentColor;
  border-radius: 10px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  opacity: 0;
  transform: rotate(8deg);
  pointer-events: none;
}

.drag-label.left { right: auto; left: 26px; transform: rotate(-8deg); }

.flip-out { transform: rotateY(90deg); transition: transform 170ms ease-in; }
.flip-in-start { transform: rotateY(-90deg); }
.flip-in { transform: rotateY(0); transition: transform 210ms ease-out; }

.choices {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-top: 26px;
}

.choice,
.next,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 58px;
  padding: 12px 20px;
  border: 2px solid var(--ink);
  border-radius: 14px;
  background: var(--card);
  box-shadow: 4px 4px 0 var(--ink);
  font-size: 19px;
  font-weight: 700;
  text-decoration: none;
  transition: transform 80ms, box-shadow 80ms;
}

.choice:active, .next:active, .button:active { transform: translate(3px, 3px); box-shadow: 1px 1px 0 var(--ink); }

.choice.actually, .next, .button.primary {
  background: var(--ink);
  color: var(--bg);
}

.choice.actually em { font-family: var(--serif); }

kbd {
  padding: 1px 7px;
  border: 1.5px solid currentColor;
  border-radius: 6px;
  font: 600 13px var(--mono);
  opacity: 0.6;
}

.next { grid-column: 1 / -1; }

.hint {
  margin-top: 14px;
  color: var(--ink-faint);
  font-size: 14px;
  text-align: center;
}

/* ---- the back of a card ---- */

.verdict {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 4px 12px;
  margin: 6px 0 14px;
}

.verdict strong { font: italic 600 30px/1.1 var(--serif); }
.verdict .who { font-weight: 700; font-size: 15px; }
.verdict.ok .who { color: var(--ok); }
.verdict.miss .who { color: var(--miss); }

.was {
  margin: 0 0 12px;
  color: var(--ink-faint);
  font: 18px/1.35 var(--serif);
}

.was.false { text-decoration: line-through; text-decoration-color: var(--miss); text-decoration-thickness: 2px; }

.truth { margin: 0 0 10px; font: 600 21px/1.35 var(--serif); }

.explain { margin: 0 0 18px; color: var(--ink-soft); }

.proof {
  border: 2px solid var(--ink);
  border-radius: 12px;
  overflow: hidden;
  background: var(--code-bg);
}

.proof-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px 8px 14px;
  border-bottom: 2px solid var(--ink);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.proof-bar span { flex: 1; color: var(--ink-soft); }

.proof-bar button {
  padding: 3px 10px;
  border: 1.5px solid var(--ink);
  border-radius: 8px;
  background: var(--card);
  font-size: 13px;
  font-weight: 700;
}

.proof-bar button.run { background: var(--ink); color: var(--bg); }

.code, .editor, .output {
  display: block;
  width: 100%;
  margin: 0;
  padding: 12px 14px;
  border: 0;
  font: 13.5px/1.6 var(--mono);
  white-space: pre;
  overflow-x: auto;
  tab-size: 2;
}

.code, .editor { background: transparent; color: var(--ink); }

.editor { resize: vertical; min-height: 140px; outline: none; }

.output {
  border-top: 2px dashed var(--line);
  background: var(--card);
  color: var(--ink);
}

.output::before {
  content: 'Output';
  display: block;
  margin-bottom: 4px;
  color: var(--ink-faint);
  font: 700 11px var(--sans);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.output .error { color: var(--miss); }

.tok-keyword { color: var(--tok-keyword); }
.tok-string { color: var(--tok-string); }
.tok-number { color: var(--tok-number); }
.tok-comment { color: var(--tok-comment); font-style: italic; }
.tok-method { color: var(--tok-method); }

.examples {
  margin: 0;
  padding: 12px 14px 12px 34px;
  border: 2px solid var(--ink);
  border-radius: 12px;
  background: var(--code-bg);
  font-family: var(--serif);
  font-size: 17px;
}

.examples li + li { margin-top: 4px; }

.source { display: inline-block; margin-top: 16px; color: var(--ink-faint); font-size: 14px; }

/* ---- results ---- */

.results { max-width: 640px; margin: 0 auto; text-align: center; }

.eyebrow { margin: 16px 0 0; color: var(--ink-soft); font-weight: 700; }

.score {
  margin: 4px 0 0;
  font: 600 clamp(84px, 20vw, 132px)/1 var(--serif);
  letter-spacing: -0.03em;
}

.score span { font-size: 0.45em; color: var(--ink-faint); }

.rank { margin: 6px 0 18px; font: italic 26px/1.3 var(--serif); }

.squares { font-size: 30px; letter-spacing: 4px; margin-bottom: 22px; }

.actions { display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; }

.when { margin: 18px 0 30px; color: var(--ink-soft); }

.review {
  margin: 0 0 30px;
  padding: 0;
  list-style: none;
  text-align: left;
  border-top: 2px solid var(--line);
}

.review li {
  display: flex;
  gap: 12px;
  align-items: baseline;
  padding: 10px 2px;
  border-bottom: 2px solid var(--line);
}

.review .mark { font-weight: 800; width: 1.2em; }
.review .mark.ok { color: var(--ok); }
.review .mark.miss { color: var(--miss); }
.review a { flex: 1; font: 18px/1.35 var(--serif); text-decoration: none; }
.review a:hover { text-decoration: underline; }
.review .tag { color: var(--ink-faint); font-size: 13px; font-weight: 700; text-transform: uppercase; }

h2.section { margin: 34px 0 12px; font: 600 24px/1.2 var(--serif); text-align: left; }

/* ---- practice and the deck ---- */

.page { max-width: 820px; margin: 0 auto; }

.page h1 { margin: 12px 0 6px; font: 600 clamp(32px, 6vw, 44px)/1.15 var(--serif); }

.lede { margin: 0 0 26px; color: var(--ink-soft); font-size: 18px; }

.tiles {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 16px;
}

.tile {
  --cat: var(--ink);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 130px;
  padding: 18px;
  border: 2px solid var(--ink);
  border-radius: 16px;
  background: var(--card);
  box-shadow: 4px 4px 0 var(--ink);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.tile::before { content: ''; position: absolute; inset: 0 0 auto; height: 6px; background: var(--cat); }
.tile strong { font: 600 24px/1.2 var(--serif); }
.tile span { color: var(--ink-faint); font-weight: 600; font-size: 14px; }
.tile:hover { transform: translate(-1px, -1px); box-shadow: 5px 5px 0 var(--ink); }

.tile[data-cat='time'] { --cat: var(--time); }
.tile[data-cat='text'] { --cat: var(--text); }
.tile[data-cat='numbers'] { --cat: var(--numbers); }
.tile[data-cat='names'] { --cat: var(--names); }
.tile[data-cat='places'] { --cat: var(--places); }
.tile[data-cat='money'] { --cat: var(--money); }
.tile[data-cat='web'] { --cat: var(--web); }

.filters { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 18px; }

.filters input {
  flex: 1 1 220px;
  min-height: 42px;
  padding: 8px 14px;
  border: 2px solid var(--ink);
  border-radius: 12px;
  background: var(--card);
  color: var(--ink);
  font: inherit;
}

.filters button {
  padding: 6px 12px;
  border: 2px solid var(--line);
  border-radius: 999px;
  background: transparent;
  font-size: 14px;
  font-weight: 700;
}

.filters button[aria-pressed='true'] { border-color: var(--ink); background: var(--ink); color: var(--bg); }

.deck-list { margin: 0; padding: 0; list-style: none; border-top: 2px solid var(--line); }

.deck-list li { border-bottom: 2px solid var(--line); }

.deck-list a {
  display: grid;
  grid-template-columns: 96px 1fr auto;
  gap: 14px;
  align-items: baseline;
  padding: 12px 2px;
  text-decoration: none;
}

.deck-list .cat { font-size: 12px; font-weight: 800; letter-spacing: 0.05em; text-transform: uppercase; }
.deck-list .claimline { font: 18px/1.35 var(--serif); }
.deck-list a:hover .claimline { text-decoration: underline; }
.deck-list .answer { font-size: 13px; font-weight: 800; color: var(--ink-faint); }
.deck-list .answer.true { color: var(--ok); }

.cat-time { color: var(--time); }
.cat-text { color: var(--text); }
.cat-numbers { color: var(--numbers); }
.cat-names { color: var(--names); }
.cat-places { color: var(--places); }
.cat-money { color: var(--money); }
.cat-web { color: var(--web); }

.prose { max-width: 640px; font-size: 18px; }
.prose p { margin: 0 0 16px; }
.prose h2 { margin: 30px 0 10px; font: 600 24px/1.2 var(--serif); }

.toast {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translate(-50%, 140%);
  padding: 10px 18px;
  border: 2px solid var(--ink);
  border-radius: 12px;
  background: var(--ink);
  color: var(--bg);
  font-weight: 700;
  opacity: 0;
  visibility: hidden;
  transition: transform 220ms ease, opacity 220ms ease, visibility 220ms;
  pointer-events: none;
}

.toast.show { transform: translate(-50%, 0); opacity: 1; visibility: visible; }

.noscript { max-width: 520px; margin: 60px auto; font: 22px/1.4 var(--serif); text-align: center; }

.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

@media (max-width: 640px) {
  .top { padding: 14px 16px 4px; }
  main { padding: 10px 16px 36px; }
  .card { padding: 24px 20px 24px; min-height: 340px; }
  .choices { gap: 10px; }
  .choice { font-size: 17px; padding: 10px 12px; }
  .choice kbd, .hint .keys { display: none; }
  .pips li { width: 14px; }
  .deck-list a { grid-template-columns: 1fr auto; }
  .deck-list .cat { grid-column: 1 / -1; }
  .watermark { font-size: 110px; }
}

@media (prefers-reduced-motion: reduce) {
  .flip-out, .flip-in, .choice, .next, .button, .toast { transition: none; }
}