:root {
  --ink: #171714;
  --soft-ink: #4b473f;
  --paper: #f3eee3;
  --paper-2: #e8dfcf;
  --vermilion: #a92f25;
  --vermilion-dark: #7f2019;
  --gold: #80642f;
  --line: rgba(23, 23, 20, 0.2);
  --sans: "Noto Sans TC", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  --serif: "Noto Serif TC", "Songti TC", "Yu Mincho", "Hiragino Mincho ProN", serif;
}

* { box-sizing: border-box; }

html { background: var(--paper); color: var(--ink); scroll-behavior: smooth; }

body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  font-family: var(--sans);
  line-height: 1.75;
  background-color: var(--paper);
  background-image:
    radial-gradient(circle at 50% 100%, transparent 22px, rgba(138, 109, 56, 0.11) 23px, rgba(138, 109, 56, 0.11) 25px, transparent 26px),
    radial-gradient(circle at 0 100%, transparent 22px, rgba(138, 109, 56, 0.08) 23px, rgba(138, 109, 56, 0.08) 25px, transparent 26px);
  background-size: 52px 26px;
}

a { color: var(--vermilion-dark); text-underline-offset: 0.18em; }
a:hover { color: var(--vermilion); }
a:focus-visible { outline: 3px solid var(--vermilion); outline-offset: 4px; }

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.65rem 1rem;
  color: white;
  background: var(--ink);
  transform: translateY(-180%);
}
.skip-link:focus { transform: translateY(0); }

.library-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 4.75rem;
  padding: 0 5vw;
  border-bottom: 1px solid var(--line);
  background: rgba(243, 238, 227, 0.96);
}
.library-brand { color: var(--ink); font: 600 1.35rem var(--serif); text-decoration: none; letter-spacing: 0.12em; }
.library-brand span { color: var(--soft-ink); font: 700 0.55rem var(--sans); letter-spacing: 0.16em; }
.library-header nav { display: flex; gap: 1.25rem; font-size: 0.82rem; }

.library-shell { width: min(72rem, calc(100% - 2rem)); margin: 0 auto; padding: 2rem 0 6rem; }
.library-breadcrumb ol { display: flex; flex-wrap: wrap; gap: 0.65rem; margin: 0 0 3rem; padding: 0; list-style: none; color: var(--soft-ink); font-size: 0.8rem; }
.library-breadcrumb li + li::before { margin-right: 0.65rem; content: "/"; color: var(--gold); }
.library-intro, .detail-hero { max-width: 52rem; margin: 0 0 3.5rem; padding: clamp(1.5rem, 5vw, 4.5rem); border-left: 4px solid var(--vermilion); background: rgba(243, 238, 227, 0.9); }
.eyebrow { margin: 0 0 0.7rem; color: var(--vermilion-dark); font-weight: 800; font-size: 0.72rem; letter-spacing: 0.16em; text-transform: uppercase; }
h1, h2 { font-family: var(--serif); }
h1 { margin: 0; font-size: clamp(2.25rem, 7vw, 4.7rem); line-height: 1.18; }
h2 { margin-top: 0; font-size: clamp(1.45rem, 3vw, 2rem); line-height: 1.35; }
.library-intro > p:last-child, .direct-answer { max-width: 45rem; color: var(--soft-ink); font-size: 1.05rem; }
.direct-answer { margin-top: 1.75rem; font-size: clamp(1.05rem, 2vw, 1.25rem); }

.library-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 18rem), 1fr)); gap: 1rem; }
.library-card, .meaning-block, .sources, .related, .error-card { padding: clamp(1.4rem, 4vw, 2.4rem); border: 1px solid var(--line); background: rgba(243, 238, 227, 0.94); }
.library-card { position: relative; overflow: hidden; transition: border-color 240ms ease, transform 240ms ease, box-shadow 240ms ease; }
.library-card:hover { border-color: rgba(127, 32, 25, 0.45); box-shadow: 0 1.25rem 3rem rgba(23, 23, 20, 0.08); transform: translateY(-0.25rem); }
.library-card > a { display: block; color: var(--ink); text-decoration: none; }
.library-card img { display: block; width: min(100%, 15rem); height: auto; aspect-ratio: 1; margin: 0 auto 1.25rem; object-fit: contain; filter: drop-shadow(0 0.75rem 1.2rem rgba(23, 23, 20, 0.12)); transition: transform 500ms cubic-bezier(.2,.75,.25,1); }
.library-card:hover img { transform: rotate(2deg) scale(1.025); }
.library-card h2 { margin: 0.25rem 0 0.75rem; }
.library-card p:last-child, .meaning-block p, .meaning-block li, .related p { color: var(--soft-ink); }
.entry-kind { margin: 0; color: var(--gold); font-size: 0.72rem; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; }

.library-detail > article { display: grid; gap: 1.25rem; }
.entry-detail { display: grid; gap: clamp(1.25rem, 3vw, 2rem); }
.entry-detail > section { padding: clamp(1.4rem, 4vw, 2.5rem); border-top: 1px solid var(--line); background: rgba(243, 238, 227, 0.88); }
.entry-hero { display: grid; grid-template-columns: minmax(0, 1fr) minmax(16rem, 26rem); align-items: center; gap: clamp(2rem, 6vw, 5rem); padding: clamp(1.5rem, 5vw, 4rem); border-left: 4px solid var(--vermilion); background: rgba(243, 238, 227, 0.94); }
.entry-hero figure { margin: 0; text-align: center; }
.entry-hero img { display: block; width: 100%; height: auto; aspect-ratio: 1; object-fit: contain; filter: drop-shadow(0 1.25rem 2rem rgba(23, 23, 20, 0.14)); animation: crest-arrive 700ms cubic-bezier(.2,.75,.25,1) both; }
.entry-hero figcaption { margin-top: 0.75rem; color: var(--soft-ink); font-size: 0.78rem; }
.entry-answer { max-width: 44rem; padding-top: 1.25rem; border-top: 1px solid var(--line); color: var(--soft-ink); font-size: clamp(1.05rem, 2vw, 1.3rem); }
.entry-detail dl { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1px; margin: 0; background: var(--line); }
.entry-detail dl div { padding: 1rem; background: var(--paper); }
.entry-detail dt { color: var(--soft-ink); font-size: 0.75rem; letter-spacing: 0.08em; }
.entry-detail dd { margin: 0.3rem 0 0; font-family: var(--serif); font-size: 1.1rem; }
.claim-list { display: grid; gap: 1rem; padding: 0; list-style: none; }
.claim-list li { padding: 1.1rem 1.25rem; border-left: 3px solid var(--gold); background: var(--paper-2); }
.claim-list b { font-family: var(--serif); }
.claim-list p { margin-bottom: 0; color: var(--soft-ink); }
@keyframes crest-arrive { from { opacity: 0; transform: scale(.94) rotate(-2deg); } to { opacity: 1; transform: scale(1) rotate(0); } }
.meaning-block ul { padding-left: 1.35rem; }
.disclaimer { padding: 1.5rem 1.75rem; border-left: 4px solid var(--gold); background: #e6dcc7; }
.disclaimer h2 { margin-bottom: 0.45rem; font-size: 1.1rem; }
.disclaimer p { margin: 0; color: #38352f; }
.citation-list, .related-list { margin: 0; padding: 0; list-style: none; }
.citation-list li { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1.5rem; padding: 0.85rem 0; border-top: 1px solid var(--line); }
.citation-list span { color: var(--soft-ink); font-size: 0.78rem; }
.related-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr)); gap: 1rem; }
.related-list li { padding: 1rem; border-top: 2px solid var(--gold); background: var(--paper-2); }
.related-list a { font: 600 1.1rem var(--serif); }

.library-error { min-height: calc(100vh - 11rem); }
.error-card { max-width: 42rem; }
.text-link { display: inline-block; margin-top: 1rem; font-weight: 700; }
.empty-state { padding: 2rem; background: rgba(243, 238, 227, 0.94); }
.library-footer { padding: 2rem 5vw; color: #f3eee3; background: var(--ink); font-size: 0.78rem; letter-spacing: 0.08em; }

@media (max-width: 40rem) {
  .library-header { align-items: flex-start; flex-direction: column; gap: 0.65rem; padding-block: 1rem; }
  .library-shell { width: min(100% - 1.25rem, 72rem); padding-top: 1.5rem; }
  .library-breadcrumb ol { margin-bottom: 1.5rem; }
  .library-intro, .detail-hero { padding: 1.4rem; }
  .entry-hero { grid-template-columns: 1fr; padding: 1.4rem; }
  .entry-hero figure { order: -1; }
  .entry-detail dl { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}