:root {
  --ink: #0f172a;
  --ink-2: #334155;
  --muted: #64748b;
  --line: #e2e8f0;
  --surface: #ffffff;
  --surface-alt: #f6f8fb;
  --accent: #1d4ed8;
  --accent-soft: #e8efff;
  --single: #2563eb;
  --multi: #7c3aed;
  --locref: #0f766e;
  --nv: #c2410c;
  --del-bg: #ffe4e6;
  --del-ink: #9f1239;
  --ins-bg: #dcfce7;
  --ins-ink: #166534;
  --nv-bg: #fef3c7;
  --nv-ink: #92400e;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(15, 23, 42, 0.06), 0 4px 16px rgba(15, 23, 42, 0.06);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--surface);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.wrap {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.wrap.narrow {
  max-width: 900px;
}

/* hero */

.hero {
  padding: 72px 0 48px;
  text-align: center;
  background:
    radial-gradient(900px 360px at 15% 0%, rgba(37, 99, 235, 0.10), transparent 70%),
    radial-gradient(700px 320px at 90% 10%, rgba(124, 58, 237, 0.08), transparent 70%),
    linear-gradient(180deg, #f5f8ff 0%, #ffffff 100%);
  border-bottom: 1px solid var(--line);
}

.hero-title {
  max-width: 980px;
  margin: 0 auto 24px;
  font-size: clamp(26px, 3.4vw, 40px);
  line-height: 1.22;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.brand {
  font-weight: 800;
  color: var(--accent);
}

.authors {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 4px 18px;
  max-width: 900px;
  margin: 0 auto 10px;
  font-size: 17px;
  color: var(--ink-2);
}

.affiliations {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2px 20px;
  margin: 0 auto 4px;
  font-size: 14px;
  color: var(--muted);
}

.footnote-line {
  margin: 0 0 24px;
  font-size: 13px;
  color: var(--muted);
}

.resource-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  transition: transform 0.15s ease, background 0.15s ease;
}

.btn:hover {
  text-decoration: none;
  background: #1e293b;
  transform: translateY(-1px);
}

.btn svg {
  width: 18px;
  height: 18px;
}

.btn-logo {
  width: 20px;
  height: 20px;
}

.btn.is-disabled {
  background: #94a3b8;
  cursor: default;
}

.btn.is-disabled:hover {
  transform: none;
}

.btn.is-disabled::after {
  content: "soon";
  margin-left: 2px;
  padding: 1px 6px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.25);
  font-size: 11px;
  font-weight: 600;
}

/* sections */

.section {
  padding: 64px 0;
}

.section.alt {
  background: var(--surface-alt);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-title {
  margin: 0 0 20px;
  font-size: 28px;
  font-weight: 700;
  text-align: center;
  letter-spacing: -0.01em;
}

.section-lead {
  max-width: 900px;
  margin: 0 auto 28px;
  color: var(--ink-2);
  text-align: center;
}

.abstract {
  margin: 0;
  color: var(--ink-2);
  text-align: justify;
  hyphens: auto;
}

.figure {
  margin: 0 auto;
  max-width: 1080px;
}

.table-scroll + .figure {
  margin-top: 40px;
}

.figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  background: #fff;
  border: 1px solid var(--line);
  padding: 12px;
}

.figure figcaption {
  max-width: 900px;
  margin: 14px auto 0;
  font-size: 14px;
  color: var(--muted);
  text-align: center;
}

/* tables */

.table-scroll {
  overflow-x: auto;
}

.data-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-size: 15px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.data-table caption {
  padding: 0 2px 10px;
  font-weight: 600;
  text-align: left;
  color: var(--ink-2);
}

.data-table th,
.data-table td {
  padding: 9px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.data-table th {
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  background: #f8fafc;
}

.data-table .num {
  text-align: right;
  font-variant-numeric: tabular-nums;
}

/* scroll on narrow screens instead of wrapping cells at hyphens */
.data-table.results th,
.data-table.results td {
  white-space: nowrap;
}

.data-table tr.group td {
  font-weight: 600;
  font-style: italic;
  color: var(--ink-2);
  background: #fbfcfe;
}

.data-table tbody tr:last-child > td,
.data-table tbody tr:nth-last-child(3) > td[rowspan="3"] {
  border-bottom: none;
}

.data-table tfoot td {
  font-weight: 700;
  border-top: 1px solid var(--line);
  border-bottom: none;
}

.data-table tr.ours td {
  background: var(--accent-soft);
}

.data-table tr.split td {
  border-top: 1px solid var(--line);
}

.dot {
  display: inline-block;
  width: 9px;
  height: 9px;
  margin-right: 8px;
  border-radius: 50%;
  vertical-align: 1px;
}

.dot.single { background: var(--single); }
.dot.multi { background: var(--multi); }
.dot.locref { background: var(--locref); }
.dot.nv { background: var(--nv); }

.results-grid {
  display: grid;
  gap: 32px;
  max-width: 960px;
  margin: 0 auto;
}

/* sample toolbar */

.toolbar {
  position: sticky;
  top: 0;
  z-index: 20;
  margin: 0 0 16px;
  padding: 12px 0;
  background: var(--surface-alt);
}

.tabs {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
}

.tab {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  font: inherit;
  text-align: left;
  color: var(--ink);
  cursor: pointer;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.tab:hover {
  border-color: #cbd5e1;
}

.tab .tab-label {
  font-weight: 600;
}

.tab .tab-sub {
  font-size: 13px;
  color: var(--muted);
}

.tab[aria-pressed="true"] {
  border-color: var(--cat, var(--accent));
  box-shadow: inset 0 0 0 1px var(--cat, var(--accent)), var(--shadow);
}

.tab[aria-pressed="true"] .tab-label {
  color: var(--cat, var(--accent));
}

.toolbar-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 12px;
}

.subtabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.subtab {
  padding: 5px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font: inherit;
  font-size: 14px;
  color: var(--ink-2);
  cursor: pointer;
}

.subtab[aria-pressed="true"] {
  border-color: var(--ink);
  background: var(--ink);
  color: #fff;
}

.segmented {
  display: inline-flex;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
}

.segmented button {
  padding: 4px 12px;
  border: none;
  border-radius: 999px;
  background: transparent;
  font: inherit;
  font-size: 14px;
  color: var(--ink-2);
  cursor: pointer;
}

.segmented button[aria-pressed="true"] {
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
}

.category-desc {
  margin: 0 0 20px;
  color: var(--ink-2);
}

/* sample cards */

.card-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.card {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 18px 18px 16px;
  border: 1px solid var(--line);
  border-top: 3px solid var(--cat, var(--accent));
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

.card-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
}

.chip {
  display: inline-block;
  padding: 1px 9px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  line-height: 20px;
  background: #f1f5f9;
  color: var(--ink-2);
}

.chip.cat {
  background: var(--cat);
  color: #fff;
}

.chip.meta {
  margin-left: auto;
  font-weight: 500;
  background: transparent;
  color: var(--muted);
}

.instruction {
  margin: 0;
  padding: 10px 14px;
  border-left: 3px solid var(--cat, var(--accent));
  border-radius: 0 8px 8px 0;
  background: #f8fafc;
  font-size: 15px;
  font-weight: 500;
}

.instruction::before {
  content: "Instruction";
  display: block;
  margin-bottom: 2px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.track {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 4px 12px;
  align-items: center;
}

.track-label {
  grid-column: 2;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-2);
}

.track-label .origin {
  padding: 0 7px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 11px;
  font-weight: 500;
  color: var(--muted);
}

.track-label .time {
  margin-left: auto;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
}

.play {
  grid-row: 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
  border: none;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  cursor: pointer;
  transition: background 0.15s ease, transform 0.15s ease;
}

.play:hover {
  transform: scale(1.05);
}

.play:disabled {
  background: #cbd5e1;
  cursor: default;
}

.play svg {
  width: 16px;
  height: 16px;
}

.play .icon-pause,
.play.is-playing .icon-play {
  display: none;
}

.play.is-playing .icon-pause {
  display: block;
}

.wave {
  grid-row: 2;
  min-height: 56px;
  border-radius: 6px;
  cursor: pointer;
}

.transcript {
  grid-column: 2;
  margin: 2px 0 0;
  font-size: 14.5px;
  line-height: 1.65;
  color: var(--ink-2);
}

.transcript:lang(zh),
.instruction:lang(zh) {
  letter-spacing: 0.02em;
}

.mark-del,
.transcript .del {
  padding: 0 2px;
  border-radius: 3px;
  background: var(--del-bg);
  color: var(--del-ink);
  text-decoration: line-through;
  text-decoration-thickness: 1px;
}

.mark-ins,
.transcript .ins {
  padding: 0 2px;
  border-radius: 3px;
  background: var(--ins-bg);
  color: var(--ins-ink);
  font-weight: 600;
}

.transcript .nv {
  padding: 0 4px;
  border-radius: 4px;
  background: var(--nv-bg);
  color: var(--nv-ink);
  font-family: var(--mono);
  font-size: 0.88em;
}

.transcript .nv.del {
  text-decoration: line-through;
}

.empty {
  grid-column: 1 / -1;
  padding: 40px;
  text-align: center;
  color: var(--muted);
}

/* findings */

.finding-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  max-width: 960px;
  margin: 0 auto;
  padding: 0;
  list-style: none;
}

.finding {
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.finding .rq {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--accent);
}

.finding .question {
  margin: 4px 0 0;
  font-size: 14px;
  font-style: italic;
  color: var(--muted);
}

.finding-callout {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  margin: 14px 0 0;
  padding: 14px 16px;
  border: 1px solid #f59e0b;
  border-radius: var(--radius);
  background: #fffbeb;
}

.finding-callout::before {
  content: "";
  flex: none;
  width: 28px;
  height: 28px;
  background: url("../img/lightbulb.svg") center / contain no-repeat;
}

.finding-callout p {
  margin: 0;
  font-size: 16px;
  line-height: 1.5;
  color: var(--ink);
}

.finding-callout b {
  color: #92400e;
}

.finding .evidence {
  margin: 14px 0 0;
  font-size: 14.5px;
  color: var(--ink-2);
}

.finding .figure {
  margin-top: 20px;
}

.finding .figure.tall {
  max-width: 680px;
}

/* citation */

.bibtex {
  position: relative;
}

.bibtex pre {
  margin: 0;
  padding: 18px 84px 18px 20px;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  border-radius: var(--radius);
  background: #0f172a;
  color: #e2e8f0;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.6;
}

.copy-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  padding: 4px 12px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.08);
  color: #e2e8f0;
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.16);
}

/* responsive */

@media (max-width: 960px) {
  .card-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 720px) {
  .hero {
    padding: 48px 0 36px;
  }

  .tabs {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .toolbar {
    position: static;
  }

  .section {
    padding: 48px 0;
  }
}