:root {
  color-scheme: light dark;
  --bg: #f1f4f2;
  --card: #ffffff;
  --text: #233731;
  --muted: #5e7169;
  --border: #dce5df;
  --note: #f4f8f5;
  --accent: #21634f;
  --accent-soft: #e6f0e9;
  --shadow: 0 4px 20px #1e413608;
  --gutter: clamp(16px, 2.2vw, 48px);
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); font: 17px/1.85 ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft JhengHei", sans-serif; overflow-wrap: anywhere; }
a { color: var(--accent); text-underline-offset: .2em; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; }
.workspace { display: grid; grid-template-columns: clamp(230px, 17vw, 290px) minmax(0, 1fr); gap: var(--gutter); padding: var(--gutter); align-items: start; }
main { min-width: 0; container: reader / inline-size; padding-bottom: 64px; }
section, #top { scroll-margin-top: 120px; }

/* Chapter navigation stays within reach while the reading area expands. */
.sidebar { position: sticky; top: var(--gutter); max-height: calc(100dvh - 2 * var(--gutter)); overflow-y: auto; scrollbar-width: thin; padding: 24px 18px; background: var(--card); border: 1px solid var(--border); border-radius: 18px; }
.overview-link { display: flex; justify-content: space-between; padding: 10px 12px; background: var(--accent-soft); border-radius: 8px; font-size: .9rem; font-weight: 650; text-decoration: none; }
.contents summary { padding: 22px 4px 12px; cursor: pointer; color: var(--muted); font-size: .8rem; }
.contents summary > span { float: right; font-size: .72rem; }
.contents ol { margin: 0; padding: 0; list-style: none; }
.contents li + li { margin-top: 4px; }
.contents li a { display: grid; grid-template-columns: 22px minmax(0, 1fr); gap: 8px; padding: 12px 8px; border-radius: 8px; color: var(--muted); font-size: .8rem; line-height: 1.65; text-decoration: none; }
.contents a:hover { background: var(--accent-soft); color: var(--accent); }
.nav-number { font-size: .7rem; color: var(--accent); font-variant-numeric: tabular-nums; padding-top: 2px; }
.sidebar-note { border-top: 1px solid var(--border); margin: 22px 0 0; padding-top: 18px; color: var(--muted); font-size: .7rem; line-height: 1.9; }

/* Paper identity and overview. */
.hero { padding: clamp(20px, 2vw, 32px); background: var(--card); border: 1px solid var(--border); border-top: 4px solid var(--accent); border-radius: 18px; box-shadow: var(--shadow); }
.hero h1 { margin: 12px 0 16px; font-size: clamp(1.6rem, 2.2vw, 2.4rem); line-height: 1.2; letter-spacing: -.035em; }
.hero p[aria-label="生成資訊"] { margin: 12px 0 0; color: var(--muted); font-size: .82rem; line-height: 1.65; }
.eyebrow { margin: 0; color: var(--accent); font-size: .72rem; font-weight: 750; letter-spacing: .14em; }
.eyebrow span { display: inline-block; margin-left: 16px; color: var(--muted); font-weight: 400; letter-spacing: .04em; }
.paper-meta { display: flex; flex-wrap: wrap; gap: 8px 20px; color: var(--muted); font-size: .82rem; }
.paper-meta span + span { padding-left: 20px; border-left: 1px solid var(--border); }
.overview { margin-top: 22px; }
.one-line { display: grid; grid-template-columns: 140px minmax(0, 1fr); gap: 24px; padding: 28px 32px; background: var(--accent-soft); border: 1px solid var(--border); border-radius: 14px; }
.one-line strong { color: var(--accent); font-size: .95rem; }
.one-line strong span { display: block; margin-top: 6px; font-size: .6rem; letter-spacing: .12em; }
.one-line p { max-width: 95ch; margin: 0; font-size: 1.08rem; line-height: 1.9; }
.overview-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin-top: 16px; }
.overview-grid > div { min-width: 0; padding: 24px 28px; background: var(--card); border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow); }
.overview-grid h2 { display: flex; align-items: center; gap: 10px; margin: 0 0 14px; color: var(--accent); font-size: .85rem; }
.overview-grid h2::before { content: ''; width: 6px; height: 16px; border-radius: 3px; background: var(--accent); opacity: .6; }
.overview-grid p, .overview-grid ul { max-width: 70ch; margin: 0; font-size: .94rem; }
.overview-grid ul { padding-left: 1.15em; }
.overview-grid li + li { margin-top: 12px; }
.overview-grid li::marker { color: var(--accent); }

/* Reading controls and passages. */
.toolbar { position: sticky; top: 0; z-index: 5; display: flex; flex-wrap: wrap; align-items: center; gap: 10px 18px; margin-top: 28px; padding: 12px 18px; border: 1px solid var(--border); border-radius: 12px; background: var(--card); box-shadow: 0 6px 24px #1e413610; }
.filter-controls { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.filter-label, .readout-count, .back-to-top { font-size: .8rem; color: var(--muted); }
.filter-label { margin-right: 8px; }
.back-to-top { margin-left: auto; }
button { min-height: 44px; border: 1px solid transparent; border-radius: 7px; padding: 8px 14px; background: var(--note); color: var(--text); font: inherit; font-size: .85rem; cursor: pointer; }
button:hover { border-color: var(--accent); }
button.active { background: var(--accent); border-color: var(--accent); color: var(--card); }
.reading-section { margin-top: 44px; }
.section-head { display: grid; grid-template-columns: 48px minmax(0, 1fr); column-gap: 18px; margin-bottom: 24px; }
.section-number { grid-row: span 2; display: grid; place-items: center; align-self: start; min-height: 48px; border: 1px solid var(--border); border-radius: 12px; background: var(--card); color: var(--accent); font-size: 1rem; font-weight: 650; font-variant-numeric: tabular-nums; }
.reading-section:target .section-number { background: var(--accent); color: var(--card); }
.section-head h2 { margin: 2px 0 10px; font-size: clamp(1.15rem, 1.6vw, 1.5rem); line-height: 1.5; text-wrap: balance; }
.section-head > p { max-width: 100ch; margin: 0; color: var(--muted); font-size: .94rem; }
.pair { display: grid; grid-template-columns: minmax(0, 1.6fr) minmax(250px, 1fr); margin: 18px 0; overflow: hidden; background: var(--card); border: 1px solid var(--border); border-radius: 14px; box-shadow: var(--shadow); }
.source { min-width: 0; padding: 28px; }
.original, .translated { min-width: 0; }
.translated { border-top: 1px solid var(--border); margin-top: 24px; padding-top: 24px; }
.annotation { min-width: 0; padding: 28px; border-left: 1px solid var(--border); background: var(--note); font-size: .94rem; line-height: 1.95; }
.annotation h3 { margin: 24px 0 10px; color: var(--accent); font-size: .83rem; }
.annotation > p:not(.passage-label) { max-width: 60ch; margin: 0 0 26px; }
.annotation > p:last-of-type { margin-bottom: 0; }
.meta-row { display: flex; flex-wrap: wrap; gap: 8px 14px; align-items: center; margin-bottom: 24px; color: var(--muted); font-size: .75rem; font-variant-numeric: tabular-nums; }
.passage-label { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 14px; color: var(--muted); font-size: .72rem; letter-spacing: .04em; font-weight: 650; }
.passage-label span { align-self: center; font-size: .58rem; font-weight: 400; letter-spacing: .1em; }
blockquote { max-width: 72ch; margin: 0; font: 1.1rem/1.9 ui-serif, Georgia, "Times New Roman", serif; }
.translation { max-width: 42em; margin: 0; line-height: 1.95; }
blockquote, .translation, .annotation > p:not(.passage-label) { white-space: pre-line; }
mark { background: #fff0b2; color: #332b15; border-radius: 2px; padding: 0; box-decoration-break: clone; -webkit-box-decoration-break: clone; }
.katex { white-space: normal; }
.katex-display { overflow-x: auto; overflow-y: hidden; padding: .3em 0; }
.empty-section { padding: 20px; border: 1px dashed var(--border); border-radius: 8px; color: var(--muted); }
.skip-link { position: absolute; top: -100px; left: 16px; z-index: 10; padding: 10px 16px; background: var(--card); }
.skip-link:focus { top: 12px; }
[hidden] { display: none !important; }

/* Figure guides and table data stay with the passage that discusses them. */
.visual-guides { grid-column: 1 / -1; min-width: 0; padding: 28px; border-top: 1px solid var(--border); }
.visual-guide + .visual-guide { margin-top: 28px; padding-top: 28px; border-top: 1px solid var(--border); }
.visual-guide h3 { display: flex; flex-wrap: wrap; align-items: baseline; gap: 8px 18px; margin: 0 0 14px; font-size: 1rem; color: var(--accent); }
.visual-guide h3 span { font-size: .78rem; color: var(--muted); font-weight: 400; }
.visual-caption { margin: 0 0 18px; text-align: left; font-size: .9rem; }
.visual-caption > span { display: block; white-space: pre-line; }
.visual-caption > span + span { margin-top: 6px; color: var(--muted); }
.visual-explanation { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px 28px; margin-top: 20px; }
.visual-explanation h4 { margin: 0 0 8px; color: var(--accent); font-size: .83rem; }
.visual-explanation p, .table-notes { margin: 0; font-size: .94rem; white-space: pre-line; }
.table-scroll { max-width: 100%; overflow-x: auto; }
.data-table { width: 100%; border-collapse: collapse; font-size: .88rem; font-variant-numeric: tabular-nums; }
.data-table th, .data-table td { padding: 10px 14px; border: 1px solid var(--border); text-align: left; white-space: pre-line; min-width: 7ch; }
.data-table th { background: var(--accent-soft); }
.data-table tbody tr:nth-child(even) { background: var(--note); }
.table-notes { margin-top: 14px; color: var(--muted); font-size: .85rem; }

/* Explanations stay close to the reading annotations. */
.glossary-entry { min-width: 0; }
.glossary-entry dt { font-size: 1.05rem; font-weight: 650; color: var(--accent); }
.term-zh { display: block; margin-top: 4px; font-size: .9rem; font-weight: 400; color: var(--text); }
.glossary-entry dd { margin: 0; }
.term-full-name { margin: 12px 0 0; font-size: .85rem; color: var(--muted); }
.term-label { margin: 20px 0 8px; font-size: .8rem; font-weight: 650; color: var(--accent); }
.term-text { margin: 0; font-size: .94rem; white-space: pre-line; }
.term-page { margin: 18px 0 0; color: var(--muted); font-size: .75rem; }
.block-terms { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-top: 16px; padding-top: 12px; border-top: 1px solid var(--border); }
.block-terms-label { margin-right: 2px; color: var(--muted); font-size: .7rem; }
.term-trigger { min-height: 0; padding: 2px 6px; border-radius: 4px; background: var(--card); font-size: .75rem; line-height: 1.4; }
.term-trigger[aria-expanded="true"] { border-color: var(--accent); color: var(--accent); }
.term-panel { position: fixed; z-index: 20; width: min(420px, calc(100vw - 32px)); max-height: min(480px, calc(100dvh - 32px)); overflow-y: auto; padding: 24px; background: var(--card); border: 1px solid var(--border); border-top: 4px solid var(--accent); border-radius: 14px; box-shadow: 0 12px 48px #0003; }
.term-panel-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 20px; }
.term-panel-header h2 { margin: 0; font-size: 1rem; color: var(--accent); }
.term-panel-content { margin: 0; }

/* Use available content width, including when a sidebar is present. */
@container reader (min-width: 1120px) {
  .overview-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .pair { grid-template-columns: minmax(0, 2.2fr) minmax(0, 1fr); }
  .source { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: 28px; align-content: start; }
  .meta-row { grid-column: 1 / -1; }
  .translated { margin: 0; padding: 0 0 0 28px; border-top: 0; border-left: 1px solid var(--border); }
}
@container reader (max-width: 760px) {
  .pair { grid-template-columns: 1fr; }
  .annotation { border-left: 0; border-top: 1px solid var(--border); }
  .visual-explanation { grid-template-columns: 1fr; }
}
@container reader (max-width: 560px) {
  .overview-grid { grid-template-columns: 1fr; }
  .one-line { grid-template-columns: 1fr; gap: 12px; }
  .one-line strong span { display: inline; margin-left: 12px; }
  .filter-controls { width: 100%; }
  .filter-label { display: none; }
  .toolbar { gap: 8px; }
}
@media (max-width: 1099px) {
  .workspace { grid-template-columns: minmax(0, 1fr); }
  .sidebar { position: static; max-height: none; padding: 18px 24px; }
  .contents summary { padding-top: 14px; }
  .contents ol { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px 20px; }
  .sidebar-note { display: none; }
}
@media (max-width: 600px) {
  body { font-size: 16px; }
  main { padding-bottom: 32px; }
  .hero { padding: 20px; }
  .eyebrow span { display: block; margin: 6px 0 0; }
  .paper-meta { gap: 6px 12px; }
  .paper-meta span + span { padding-left: 0; border: 0; }
  .contents ol { grid-template-columns: 1fr; }
  .one-line, .overview-grid > div, .source, .annotation, .visual-guides { padding: 22px; }
  .toolbar { padding: 10px; }
  button { padding: 8px 10px; }
  .section-head { grid-template-columns: 36px minmax(0, 1fr); gap: 0 12px; }
  .section-number { min-height: 36px; border-radius: 8px; font-size: .8rem; }
  .section-head > p { grid-column: 1 / -1; margin-top: 8px; }
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #17221e; --card: #202e27; --text: #e4ece7; --muted: #afbeb5; --border: #3b4e42; --note: #25372c; --accent: #98cfb7; --accent-soft: #2c4234; --shadow: none; }
  mark { background: #665322; color: #fff2c2; }
}
@media print {
  :root { color-scheme: light; --bg: white; --card: white; --text: #111; --muted: #444; --border: #ccc; --note: white; --accent: #254c3e; --accent-soft: white; --shadow: none; }
  body { font-size: 11pt; }
  .workspace { display: block; padding: 0; }
  main { container-type: normal; padding: 0; }
  .sidebar, .toolbar, .skip-link, .term-panel, .block-terms { display: none; }
  .hero { padding: 0 0 20px; border: 0; }
  .hero h1 { font-size: 24pt; }
  .hero, .pair, .overview-grid > div { border-radius: 0; }
  .pair { display: block; overflow: visible; }
  .source, .annotation, .visual-guides { padding: 16px; }
  .annotation { border-left: 0; border-top: 1px solid var(--border); }
  .section-head, h2, h3, .passage-label { break-after: avoid; }
  p, blockquote { orphans: 3; widows: 3; }
  mark { background: #eee; color: #111; font-weight: 650; }
  .katex-display { overflow: visible; }
  .table-scroll { overflow: visible; }
  .data-table { font-size: 9pt; }
  .data-table tr { break-inside: avoid; }
}