:root {
  --ink: #1c1714;
  --muted: #6b5e53;
  --paper: #fffdf8;
  --sheet: #f6efe4;
  --line: #e4d5c3;
  --coral: #e25b16;
  --coral-soft: #fff1e8;
  --teal: #0f6e6b;
  --teal-soft: #e7f5f3;
  --navy: #1e3a5f;
  --gold: #b7791f;
  --gold-soft: #fff6e4;
  --rose: #9f1239;
  --ok: #166534;
  --ok-soft: #ecfdf3;
  --bad: #9f1239;
  --bad-soft: #fff1f2;
  --shadow: 0 18px 40px rgba(60, 36, 12, 0.08);
  --serif: "Source Serif 4", "Noto Serif SC", Georgia, serif;
  --sans: "Outfit", "Noto Sans SC", sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--sans);
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, #ffe8d2 0%, transparent 55%),
    radial-gradient(900px 400px at 100% 0%, #d9f3ef 0%, transparent 50%),
    #f3ecdf;
  min-height: 100vh;
}
button, input, textarea { font: inherit; color: inherit; }
a { color: var(--navy); }

.top {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  gap: 12px;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: rgba(255, 253, 248, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}
.brand { min-width: 0; }
.brand small { display: block; color: var(--coral); font-weight: 700; letter-spacing: 0.04em; font-size: 12px; }
.brand strong { display: block; font-size: 16px; }
.tools { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; }
.btn {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 999px;
  padding: 7px 12px;
  cursor: pointer;
  text-decoration: none;
  font-weight: 650;
  font-size: 13px;
}
.btn.is-on, .btn.primary { background: var(--ink); color: #fff; border-color: var(--ink); }
.btn.teal { background: var(--teal); color: #fff; border-color: var(--teal); }
.btn:disabled { opacity: 0.45; cursor: default; }

.shell { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 14px; padding: 14px; align-items: start; }
.shell.has-word { grid-template-columns: 220px minmax(0, 1fr) 300px; }
.rail, .dock { position: sticky; top: 74px; }
.rail {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 10px;
  box-shadow: var(--shadow);
  max-height: calc(100vh - 90px);
  overflow: auto;
}
.rail-label {
  margin: 10px 8px 4px;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--muted);
}
.rail a {
  display: grid;
  grid-template-columns: 36px 1fr;
  gap: 8px;
  align-items: center;
  text-decoration: none;
  color: inherit;
  padding: 8px;
  border-radius: 12px;
}
.rail a.is-on { background: var(--coral-soft); }
.rail .no {
  width: 36px; height: 36px; border-radius: 10px;
  display: grid; place-items: center;
  background: var(--sheet); font-weight: 800; color: var(--coral);
}
.rail small { display: block; color: var(--muted); font-size: 12px; }
.rail strong { font-size: 13px; }

.sheet {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.sheet-head {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 12px;
  align-items: end;
  padding: 18px 20px 8px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, #fff 0%, #fff8f2 100%);
}
.unit-flag {
  background: var(--coral);
  color: #fff;
  border-radius: 12px;
  padding: 8px 10px;
  font-weight: 800;
  line-height: 1.1;
}
.unit-flag span { display: block; font-size: 11px; font-weight: 650; opacity: 0.85; }
.sheet-head h1 { margin: 0; font-family: var(--serif); font-size: 34px; letter-spacing: -0.03em; }
.sheet-head p { margin: 2px 0 0; color: var(--muted); }
.page-stamp { font-family: var(--serif); font-size: 28px; color: var(--coral); font-weight: 700; }

.stage { padding: 8px 22px 28px; }
.step-focus { margin: 8px 0 14px; font-weight: 750; color: var(--coral); }
.pager {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}
.spread { display: block; }
.col { padding: 16px 18px 22px; }
.col.side { background: #fff8f3; border-right: 1px solid var(--line); }
.block { margin: 0 0 16px; }
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--teal);
  margin: 0 0 6px;
}
.kicker.grammar { color: var(--navy); }
.kicker.reading { color: var(--rose); }
.kicker.speaking { color: var(--gold); }
.kicker.values { color: var(--coral); }

.coach {
  background: var(--teal-soft);
  border-radius: 14px;
  padding: 10px 12px;
  margin: 0 0 12px;
}
.coach b { color: var(--teal); }
.coach p { margin: 4px 0 0; }

.goals { display: grid; gap: 8px; }
.goal {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 8px 10px;
}
.goal span { display: block; font-size: 11px; font-weight: 800; letter-spacing: 0.06em; color: var(--coral); }
.gallery { display: grid; grid-template-columns: 1fr; gap: 12px; }
.gallery figure, .hero figure {
  margin: 0;
  background: var(--sheet);
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--line);
}
.gallery img, .hero img, .portrait img {
  width: 100%;
  height: auto;
  max-height: none;
  display: block;
  object-fit: contain;
  background: var(--sheet);
}
.gallery figcaption, .hero figcaption { padding: 6px 8px 8px; font-size: 12px; color: var(--muted); }
.portrait { display: grid; grid-template-columns: minmax(160px, 280px) 1fr; gap: 12px; align-items: start; margin: 0 0 14px; }
.portrait img { border-radius: 14px; border: 1px solid var(--line); background: var(--sheet); }
.missing-art {
  min-height: 140px;
  display: grid;
  place-items: center;
  padding: 12px;
  text-align: center;
  color: var(--muted);
  background:
    linear-gradient(135deg, #ffe8d2, #e7f5f3);
}

.prose, .say, .piece p.en, .line .en {
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.55;
}
.zh { color: #7c4a2d; font-size: 14px; line-height: 1.55; margin: 4px 0 0; }
.zh[hidden] { display: none; }
.piece, .line {
  padding: 10px 0;
  border-top: 1px dashed var(--line);
}
.piece.solo { border-top: 0; }
.piece.solo .en { font-size: 22px; }
.vocab-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px;
}
.vocab-word { margin: 0; font-family: var(--serif); font-size: 48px; letter-spacing: -0.03em; }
.vocab-word.is-long { font-size: 28px; line-height: 1.25; letter-spacing: 0; }
.vocab-zh { font-size: 20px; margin: 6px 0; }
.before-line { color: var(--muted); font-size: 14px; margin: 0 0 8px; }
.match-figure { display: flex; justify-content: center; background: var(--sheet); }
.match-figure img { width: auto; max-width: 100%; max-height: 42vh; height: auto; object-fit: contain; margin: 0 auto; }
.match-q { font-family: var(--serif); font-size: 22px; line-height: 1.45; margin: 12px 0; }
.match-words .opt { font-size: 20px; padding: 12px 14px; }
.match-words .opt.is-bad { background: var(--bad-soft); border-color: var(--bad); }
.match-words .opt:disabled { cursor: default; }
.line .en { font-size: 26px; }
.who { font-size: 12px; font-weight: 800; color: var(--navy); }
.w {
  border: 0;
  background: transparent;
  padding: 0 1px;
  margin: 0;
  cursor: pointer;
  border-radius: 4px;
  font: inherit;
  color: inherit;
}
.w:hover, .w.is-on { background: #ffe08a; }
.line { display: grid; grid-template-columns: 28px 1fr; gap: 8px; }
.play {
  width: 28px; height: 28px; border-radius: 50%;
  border: 1px solid var(--line); background: #fff; cursor: pointer;
}

.media {
  background: #111;
  border-radius: 14px;
  overflow: hidden;
}
.media video, .media audio { width: 100%; display: block; }
.media p { color: #f6efe4; margin: 0; padding: 8px 10px; font-size: 13px; }
.audio-row { display: grid; gap: 8px; }
.audio-row label { font-size: 13px; font-weight: 700; }

.quiz {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 12px;
}
.quiz h3 { margin: 0 0 8px; font-size: 16px; }
.item { padding: 10px 0; border-top: 1px solid var(--line); }
.item:first-of-type { border-top: 0; }
.q { margin: 0 0 8px; font-weight: 650; }
.opts { display: grid; gap: 8px; }
.opt {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 7px 10px;
  cursor: pointer;
  text-align: left;
}
.opt.is-pick { border-color: var(--navy); background: #eef3fb; }
.item.is-ok .opt.is-pick { background: var(--ok-soft); border-color: var(--ok); }
.item.is-bad .opt.is-pick { background: var(--bad-soft); border-color: var(--bad); }
.gap {
  width: min(100%, 420px);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 10px;
  background: #fff;
}
.explain { margin: 8px 0 0; font-size: 14px; background: var(--gold-soft); border-radius: 10px; padding: 8px 10px; }
.extend { margin: 6px 0 0; font-size: 14px; }
.score {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  align-items: center;
  background: var(--ink);
  color: #fff;
  border-radius: 12px;
  padding: 10px 12px;
  margin-top: 8px;
}
.actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }

.dock {
  display: none;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 12px;
  box-shadow: var(--shadow);
  max-height: calc(100vh - 90px);
  overflow: auto;
}
.shell.has-word .dock { display: block; }
.dock h2 { margin: 0 0 8px; font-size: 16px; }
.dict-empty { color: var(--muted); font-size: 14px; }
.ipa { color: var(--teal); font-weight: 700; }
.study {
  margin-top: 12px;
  background: var(--coral-soft);
  border-radius: 14px;
  padding: 10px;
}
.study[hidden] { display: none; }
.rule {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}
.rule td { border-top: 1px solid var(--line); padding: 8px 6px; vertical-align: top; }
.rule td:first-child { font-weight: 800; color: var(--navy); width: 28%; }

.hub { max-width: 1080px; margin: 0 auto; padding: 28px 16px 60px; }
.hub h1 { font-family: var(--serif); font-size: 48px; margin: 6px 0; letter-spacing: -0.03em; }
.lead { font-size: 18px; max-width: 68ch; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 12px; }
.card {
  display: block;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 14px;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow);
  min-height: 140px;
}
.card .no { color: var(--coral); font-weight: 800; }
.card h2 { margin: 4px 0; font-size: 20px; font-family: var(--serif); }
.card p { margin: 0; color: var(--muted); font-size: 14px; }
.links { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.note { font-size: 14px; color: var(--muted); }

@media (max-width: 1040px) {
  .shell, .shell.has-word { grid-template-columns: 1fr; }
  .dock { display: block; }
  .rail, .dock { position: static; max-height: none; }
  .spread { grid-template-columns: 1fr; }
  .col.side { border-right: 0; border-bottom: 1px solid var(--line); }
  .portrait { grid-template-columns: 1fr; }
  .portrait img { height: auto; width: 100%; }
}