:root {
  --paper: #f4efe4;
  --paper-deep: #ebe4d5;
  --ink: #1c2a4a;
  --teal: #1f6f66;
  --gold: #c4a15a;
  --line: rgba(28, 42, 74, 0.18);
  --muted: #5f665f;
  --white: #fffdf8;
  --shadow: 0 18px 45px rgba(28, 42, 74, 0.1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", system-ui, sans-serif;
  line-height: 1.8;
  letter-spacing: 0.02em;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.32;
  background-image: linear-gradient(rgba(28,42,74,.07) 1px, transparent 1px), linear-gradient(90deg, rgba(28,42,74,.07) 1px, transparent 1px);
  background-size: 24px 24px;
  mask-image: linear-gradient(to bottom, black, transparent 68%);
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; }
.container { width: min(1120px, calc(100% - 2rem)); margin-inline: auto; }
.skip-link { position: absolute; left: -9999px; top: 0; }
.skip-link:focus { left: 1rem; top: 1rem; z-index: 10; padding: .5rem .8rem; background: var(--ink); color: var(--white); }
.site-header { position: relative; border-bottom: 1px solid var(--line); background: rgba(244,239,228,.92); }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 4.5rem; }
.brand { text-decoration: none; font-weight: 800; letter-spacing: .14em; white-space: nowrap; }
.brand small { display: block; color: var(--teal); font-size: .68rem; letter-spacing: .2em; font-weight: 600; line-height: 1.1; }
.nav { display: flex; gap: .2rem; align-items: center; }
.nav a { padding: .45rem .55rem; text-decoration: none; font-size: .92rem; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--teal); }
.nav a[aria-current="page"] { font-weight: 800; border-bottom: 2px solid var(--gold); }
main { position: relative; }
.hero { padding: 4rem 0 4.5rem; }
.hero-grid { display: grid; gap: 2.25rem; align-items: center; }
.eyebrow { margin: 0 0 .8rem; color: var(--teal); font-size: .8rem; font-weight: 800; letter-spacing: .18em; }
h1, h2, h3 { line-height: 1.28; letter-spacing: .04em; }
h1 { margin: 0 0 1.25rem; font-size: clamp(2.25rem, 9vw, 4.6rem); }
h2 { margin: 0 0 1rem; font-size: clamp(1.55rem, 4vw, 2.4rem); }
h3 { margin: 0 0 .55rem; font-size: 1.2rem; }
p { margin: 0 0 1rem; }
.lead { max-width: 42rem; color: #39435a; font-size: 1.12rem; }
.hero-rule { width: 5rem; height: 3px; margin: 1.7rem 0; background: var(--gold); }
.actions { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 1.5rem; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 2.8rem; padding: .6rem 1rem; border: 1px solid var(--ink); border-radius: 2px; text-decoration: none; font-weight: 700; }
.button--primary { color: var(--white); background: var(--ink); }
.button--secondary { color: var(--ink); background: transparent; }
.button--disabled { color: #7c7a70; border-color: #bbb4a5; background: #e6e0d4; cursor: not-allowed; }
.cover-frame { width: min(72vw, 340px); margin-inline: auto; padding: .65rem; background: var(--white); border: 1px solid var(--line); box-shadow: var(--shadow); transform: rotate(1.2deg); }
.cover-frame img { width: 100%; }
.section { padding: 4rem 0; border-top: 1px solid var(--line); }
.section--deep { background: rgba(235,228,213,.55); }
.section-head { display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: 1rem; margin-bottom: 1.6rem; }
.section-head p { max-width: 38rem; color: var(--muted); margin: 0; }
.kicker { color: var(--gold); font-size: .82rem; font-weight: 800; letter-spacing: .16em; }
.grid { display: grid; gap: 1rem; }
.card { padding: 1.35rem; background: rgba(255,253,248,.78); border: 1px solid var(--line); }
.card--featured { border-top: 4px solid var(--teal); box-shadow: 0 8px 20px rgba(28,42,74,.05); }
.card p:last-child { margin-bottom: 0; }
.status { display: inline-block; margin-bottom: .8rem; color: var(--teal); font-size: .82rem; font-weight: 800; letter-spacing: .08em; }
.book-code { float: right; color: var(--muted); font-size: .75rem; letter-spacing: .12em; }
.meta-list { display: grid; grid-template-columns: max-content 1fr; gap: .35rem .9rem; margin: 1.2rem 0; font-size: .94rem; }
.meta-list dt { color: var(--muted); }
.meta-list dd { margin: 0; font-weight: 700; }
.pill-list { display: flex; flex-wrap: wrap; gap: .5rem; padding: 0; margin: 1.1rem 0; list-style: none; }
.pill-list li { padding: .35rem .65rem; color: var(--teal); border: 1px solid rgba(31,111,102,.35); background: rgba(31,111,102,.06); font-size: .9rem; }
.note { padding: 1rem 1.1rem; border-left: 3px solid var(--gold); background: rgba(196,161,90,.1); }
.two-col { display: grid; gap: 1.5rem; }
.process { counter-reset: process; display: grid; gap: 1rem; padding: 0; list-style: none; }
.process li { counter-increment: process; display: grid; grid-template-columns: 2rem 1fr; gap: .8rem; }
.process li::before { content: counter(process, decimal-leading-zero); color: var(--gold); font-weight: 800; }
.site-footer { position: relative; padding: 2rem 0; border-top: 1px solid var(--line); color: #4f5662; font-size: .86rem; }
.footer-grid { display: grid; gap: .5rem; }
.footer-grid p { margin: 0; }
.footer-brand { color: var(--ink); font-weight: 800; }
.breadcrumb { padding-top: 1.5rem; color: var(--muted); font-size: .85rem; }
.breadcrumb a { color: var(--teal); }
.book-page { padding: 2rem 0 4rem; }
.book-intro { display: grid; gap: 2rem; align-items: start; }
.book-cover { width: min(70vw, 360px); margin-inline: auto; }
.book-copy h1 { font-size: clamp(2rem, 7vw, 3.6rem); }
.footer-link { color: var(--teal); text-underline-offset: .2em; }
@media (min-width: 680px) {
  .container { width: min(1120px, calc(100% - 4rem)); }
  .hero-grid, .book-intro { grid-template-columns: minmax(0, 1.12fr) minmax(260px, .88fr); }
  .hero { padding: 6rem 0; }
  .cover-frame { width: min(100%, 390px); }
  .grid--three { grid-template-columns: repeat(3, 1fr); }
  .grid--two, .two-col { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 2fr; align-items: start; }
}
@media (min-width: 980px) {
  .header-inner { min-height: 5rem; }
  .nav { gap: .7rem; }
  .nav a { padding-inline: .7rem; }
  .section { padding: 5.5rem 0; }
}

.promo-player {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  background: var(--ink);
}