:root {
  --bg: #1a1612;
  --bg-elev: #241f19;
  --ink: #ebe4d6;
  --ink-dim: #a89b88;
  --accent: #c4a574;
  --line: rgba(235, 228, 214, 0.12);
  --prose-size: 1.125rem;
  --prose-lh: 1.85;
  --pad: max(1rem, env(safe-area-inset-left));
  --pad-r: max(1rem, env(safe-area-inset-right));
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f3ecdf;
    --bg-elev: #fffaf2;
    --ink: #2a241c;
    --ink-dim: #6b5f50;
    --accent: #8b5a2b;
    --line: rgba(42, 36, 28, 0.12);
  }
}

* {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--bg);
  color: var(--ink);
  font-family: "Noto Sans TC", system-ui, sans-serif;
  line-height: 1.5;
}

.top {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem var(--pad-r) 0.75rem var(--pad);
  padding-top: max(0.75rem, env(safe-area-inset-top));
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.brand {
  font-family: "Noto Serif TC", serif;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.85rem;
}

.toc-toggle {
  appearance: none;
  border: 1px solid var(--line);
  background: var(--bg-elev);
  color: var(--ink);
  border-radius: 999px;
  padding: 0.4rem 0.9rem;
  font: inherit;
  font-size: 0.85rem;
}

.toc {
  border-bottom: 1px solid var(--line);
  background: var(--bg-elev);
  padding: 0.75rem var(--pad) 1rem;
  max-height: 50dvh;
  overflow: auto;
}

.toc ol,
.chapter-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.toc a,
.chapter-list a {
  display: flex;
  gap: 0.75rem;
  padding: 0.65rem 0;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
}

.toc .n,
.chapter-list .n {
  color: var(--accent);
  font-variant-numeric: tabular-nums;
  flex: 0 0 auto;
}

.page {
  max-width: 40rem;
  margin: 0 auto;
  padding: 1.5rem var(--pad) 4rem var(--pad-r);
}

.home .hero-title {
  font-family: "Noto Serif TC", serif;
  font-weight: 700;
  font-size: clamp(1.6rem, 6vw, 2.2rem);
  line-height: 1.25;
  margin: 0.5rem 0 0.75rem;
}

.hero-lead {
  color: var(--ink-dim);
  margin: 0 0 2rem;
}

.chapter-list a {
  padding: 1rem 0;
  align-items: baseline;
}

.chapter-list .t {
  font-family: "Noto Serif TC", serif;
  font-weight: 600;
}

.fine {
  margin-top: 2.5rem;
  color: var(--ink-dim);
  font-size: 0.8rem;
}

.prose {
  font-family: "Noto Serif TC", serif;
  font-size: var(--prose-size);
  line-height: var(--prose-lh);
  letter-spacing: 0.02em;
}

.prose h1,
.prose h2,
.prose h3 {
  font-weight: 700;
  line-height: 1.35;
  margin: 2rem 0 0.85rem;
}

.prose h1 {
  font-size: 1.55rem;
}

.prose h2 {
  font-size: 1.25rem;
  color: var(--accent);
}

.prose p {
  margin: 0 0 1.1rem;
}

.prose blockquote {
  margin: 1.25rem 0;
  padding: 0.25rem 0 0.25rem 1rem;
  border-left: 3px solid var(--accent);
  color: var(--ink-dim);
}

.prose hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 2rem 0;
}

.prose strong {
  font-weight: 700;
  color: var(--accent);
}

.prose code {
  font-family: ui-monospace, monospace;
  font-size: 0.9em;
  background: var(--bg-elev);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 1.25rem 0;
}

.prose th,
.prose td {
  border: 1px solid var(--line);
  padding: 0.45rem 0.55rem;
  text-align: left;
}

.pager {
  position: sticky;
  bottom: 0;
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.75rem var(--pad) max(0.75rem, env(safe-area-inset-bottom));
  background: color-mix(in srgb, var(--bg) 94%, transparent);
  backdrop-filter: blur(10px);
  border-top: 1px solid var(--line);
}

.nav-btn {
  flex: 1;
  text-align: center;
  text-decoration: none;
  color: var(--ink);
  background: var(--bg-elev);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.75rem 0.5rem;
  font-size: 0.8rem;
  line-height: 1.35;
}

.nav-btn.disabled {
  opacity: 0.35;
}