:root {
  --bg: #fafaf7;
  --bg-elevated: #ffffff;
  --ink: #0e1116;
  --ink-soft: #3a4150;
  --ink-mute: #6b7380;
  --line: #e6e3da;
  --line-strong: #d6d2c4;
  --accent: #1f3b6d;
  --accent-soft: #e8eef9;
  --tag-bg: #efece3;
  --tag-ink: #2c2f37;
  --orig: #2f6d4f;
  --orig-bg: #e8f3ec;
  --mixed: #b87c1c;
  --mixed-bg: #fbf0d6;
  --restored: #1f3b6d;
  --restored-bg: #e7edf8;
  --max: 1180px;
  --radius: 14px;
  --shadow: 0 1px 0 rgba(20, 22, 28, 0.04), 0 8px 24px rgba(20, 22, 28, 0.05);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue",
    "PingFang SC", "Hiragino Sans", "Noto Sans CJK SC", "Microsoft YaHei",
    Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 32px;
}

a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(31, 59, 109, 0.25);
  transition: border-color 0.15s ease;
}
a:hover { border-bottom-color: var(--accent); }

code {
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 0.92em;
  background: rgba(20, 22, 28, 0.05);
  padding: 0 0.3em;
  border-radius: 4px;
}

em { font-style: italic; color: var(--ink-soft); }

/* ===== Hero ===== */
.hero {
  padding: 96px 0 72px;
  background:
    radial-gradient(1100px 540px at 50% -20%, #f1ecdb 0%, transparent 60%),
    linear-gradient(180deg, #fbf9f2 0%, var(--bg) 100%);
  border-bottom: 1px solid var(--line);
}
.hero .eyebrow {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: 18px;
}
.hero h1 {
  font-size: 2.85rem;
  font-weight: 650;
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin: 0 0 22px;
  color: var(--ink);
}
.hero .subtitle {
  max-width: 760px;
  font-size: 1.08rem;
  color: var(--ink-soft);
  margin: 0 0 26px;
}
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
}
.tag {
  display: inline-flex;
  align-items: center;
  background: var(--tag-bg);
  color: var(--tag-ink);
  font-size: 0.85rem;
  padding: 5px 12px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
}
.tag sup { font-size: 0.7em; }
.hero-nav {
  display: flex;
  gap: 28px;
  font-size: 0.95rem;
}
.hero-nav a { border-bottom: none; color: var(--ink-soft); }
.hero-nav a:hover { color: var(--accent); }

/* ===== Sections ===== */
section {
  padding: 64px 0 24px;
  border-bottom: 1px solid var(--line);
}
section:last-of-type { border-bottom: none; }
h2 {
  font-size: 1.65rem;
  font-weight: 650;
  letter-spacing: -0.01em;
  margin: 0 0 18px;
}
h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 0 0 12px;
  color: var(--ink);
}
.section-lead {
  max-width: 880px;
  color: var(--ink-soft);
  margin-bottom: 28px;
}

/* ===== Method ===== */
.method-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
  margin-top: 12px;
}
.method-card {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 22px 18px;
  box-shadow: var(--shadow);
}
.method-card h3 { margin-bottom: 8px; }
.method-card p {
  font-size: 0.93rem;
  color: var(--ink-soft);
  margin: 0;
  line-height: 1.62;
}

/* ===== Samples ===== */
.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
  margin-bottom: 28px;
  font-size: 0.88rem;
  color: var(--ink-soft);
}
.legend .dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-right: 6px;
  vertical-align: middle;
}
.dot-original { background: var(--orig); }
.dot-mixed { background: var(--mixed); }
.dot-restored { background: var(--restored); }

.dataset-title {
  margin: 36px 0 16px;
  padding-top: 12px;
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--ink);
  border-top: 1px dashed var(--line);
  padding-top: 22px;
}
.dataset-title:first-of-type { border-top: none; padding-top: 0; }

.sample-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.sample-card {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 22px;
  box-shadow: var(--shadow);
}
.sample-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}
.sample-id {
  font-family: "SF Mono", Menlo, monospace;
  font-size: 0.92rem;
  color: var(--accent);
  font-weight: 600;
}
.sample-source {
  font-size: 0.93rem;
  color: var(--ink-soft);
  flex: 1 1 auto;
  word-break: break-all;
}
.sample-stats {
  font-size: 0.82rem;
  color: var(--ink-mute);
  background: var(--accent-soft);
  padding: 2px 10px;
  border-radius: 999px;
  white-space: nowrap;
}

.audio-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}
@media (max-width: 820px) {
  .audio-row { grid-template-columns: 1fr; }
}

.audio-block {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 12px 12px 10px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: #fdfcf6;
}
.audio-block.original { border-color: rgba(47, 109, 79, 0.3); background: var(--orig-bg); }
.audio-block.mixed    { border-color: rgba(184, 124, 28, 0.3); background: var(--mixed-bg); }
.audio-block.restored { border-color: rgba(31, 59, 109, 0.3); background: var(--restored-bg); }

.audio-block label {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.audio-block.original label { color: var(--orig); }
.audio-block.mixed label    { color: var(--mixed); }
.audio-block.restored label { color: var(--restored); }

.audio-block audio {
  width: 100%;
  height: 36px;
}

.pipeline {
  margin-top: 12px;
}
.pipeline summary {
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--ink-mute);
  user-select: none;
  padding: 4px 0;
}
.pipeline summary:hover { color: var(--ink-soft); }
.pipeline[open] summary { color: var(--ink); }
.pipeline img {
  display: block;
  width: 100%;
  margin-top: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

/* ===== Previous epoch collapsible ===== */
.prev-epoch {
  margin-top: 36px;
  padding: 18px 22px;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.prev-epoch > summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  color: var(--ink-soft);
  user-select: none;
  padding: 4px 0;
  list-style: revert;
}
.prev-epoch > summary:hover { color: var(--accent); }
.prev-epoch[open] > summary {
  color: var(--ink);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}
.prev-epoch-note {
  margin: 0 0 22px;
  font-size: 0.9rem;
  color: var(--ink-mute);
  line-height: 1.65;
}
.prev-epoch .dataset-title {
  margin-top: 22px;
}
.prev-epoch .dataset-title:first-of-type {
  margin-top: 0;
}

/* ===== Repo callout ===== */
.repo-callout {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  padding: 14px 18px;
  margin: 0 0 22px;
  background: linear-gradient(180deg, #f3eee0 0%, #ece6d2 100%);
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--accent);
  border-radius: 12px;
  font-size: 0.95rem;
  color: var(--ink);
}
.repo-callout strong {
  font-weight: 650;
}
.repo-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: #395289;
  color: #fdfcf6 !important;
  border: none;
  border-radius: 8px;
  font-family: "SF Mono", Menlo, monospace;
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
  box-shadow: 0 1px 0 rgba(20, 22, 28, 0.04), 0 4px 14px rgba(57, 82, 137, 0.28);
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}
.repo-link:hover {
  background: #2c3f6c;
  transform: translateY(-1px);
  box-shadow: 0 1px 0 rgba(20, 22, 28, 0.04), 0 6px 20px rgba(57, 82, 137, 0.42);
}
.repo-link-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  border-radius: 3px;
  background: #fdfcf6;
  padding: 1px;
  box-sizing: border-box;
}
.repo-link svg {
  flex-shrink: 0;
}

/* ===== Architecture figure ===== */
.arch-figure {
  margin: 8px 0 0;
  padding: 18px;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.arch-figure svg {
  display: block;
  width: 100%;
  height: auto;
  max-width: 1080px;
  margin: 0 auto;
}
.arch-figure figcaption {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 0.88rem;
  color: var(--ink-mute);
  text-align: center;
}

.block-figures {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-top: 18px;
}
@media (max-width: 820px) {
  .block-figures { grid-template-columns: 1fr; }
}
.block-card {
  margin: 0;
  padding: 18px;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.block-title {
  margin: 0 0 4px;
  font-size: 1rem;
  font-weight: 650;
  color: var(--ink);
}
.block-sub {
  margin: 0 0 12px;
  font-size: 0.84rem;
  color: var(--ink-mute);
  line-height: 1.55;
}
.block-card svg {
  display: block;
  width: 100%;
  height: auto;
}

/* ===== Notes ===== */
.notes {
  padding-left: 22px;
  color: var(--ink-soft);
}
.notes li { margin-bottom: 8px; }

/* ===== References ===== */
.references {
  padding-left: 22px;
  color: var(--ink-soft);
  font-size: 0.94rem;
}
.references li {
  margin-bottom: 14px;
  line-height: 1.65;
}
.references li::marker { color: var(--ink-mute); }
.ref-title {
  display: inline;
  color: var(--ink);
  font-weight: 500;
}
.ref-venue {
  color: var(--ink-mute);
  font-style: italic;
}
.ref-link {
  display: inline-block;
  margin-left: 6px;
  padding: 1px 8px;
  font-family: "SF Mono", Menlo, monospace;
  font-size: 0.78rem;
  color: var(--accent);
  background: var(--accent-soft);
  border: none;
  border-radius: 4px;
  letter-spacing: 0.02em;
  vertical-align: middle;
}
.ref-link:hover {
  background: var(--accent);
  color: #fdfcf6;
  border: none;
}

/* ===== Footer ===== */
footer {
  padding: 36px 0 56px;
  border-top: 1px solid var(--line);
  background: #f4f1e7;
  font-size: 0.88rem;
  color: var(--ink-mute);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

@media (max-width: 720px) {
  .container { padding: 0 20px; }
  .hero { padding: 64px 0 48px; }
  .hero h1 { font-size: 2.1rem; }
}