/* ============================================================
   Scholarly Style — for 24shi / historical analysis projects
   Ink-dark, serious, generous whitespace, serif body text.
   ============================================================ */
@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;600;700&family=Noto+Sans+SC:wght@400;500;700&display=swap');

:root {
  --ink: #1a1a1a;
  --ink-light: #555;
  --ink-muted: #888;
  --bg: #faf9f7;
  --bg-warm: #f5f2ed;
  --border: #e0dcd5;
  --accent: #8B4513;
  --serif: 'Noto Serif SC', 'Source Han Serif SC', 'STSong', 'SimSun', serif;
  --sans: 'Noto Sans SC', 'Source Han Sans SC', 'STHeiti', 'Microsoft YaHei', sans-serif;
  --max-width: 42rem;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { font-size: 18px; }

body {
  font-family: var(--serif);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
}

/* ── Header ── */
.atlas-header {
  padding: 5rem 2rem 3rem;
  text-align: center;
  max-width: var(--max-width);
  margin: 0 auto;
}
.atlas-header h1 {
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  margin-bottom: 0.5rem;
  font-family: var(--sans);
}
.atlas-header .subtitle {
  font-size: 1rem;
  color: var(--ink-light);
  font-family: var(--serif);
  font-style: italic;
}

/* Breadcrumb */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--ink-muted);
  margin-bottom: 1.5rem;
  font-family: var(--sans);
  text-align: left;
}
.breadcrumb a {
  color: var(--ink-light);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
}
.breadcrumb a:hover { color: var(--ink); border-color: var(--ink); }
.breadcrumb .breadcrumb-sep { margin: 0 0.4rem; color: var(--border); }

/* ── Timeline River (Index) ── */
.timeline-river {
  padding: 2rem 2rem 5rem;
  max-width: 64rem;
  margin: 0 auto;
}

/* Dynasty axis */
.dynasty-axis {
  margin-bottom: 3rem;
}
.axis-strip {
  position: relative;
  height: 3rem;
}
.dynasty-band {
  position: absolute;
  bottom: 0;
  height: 2.5rem;
  background: var(--bg-warm);
  border-right: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
}
.dynasty-label {
  font-size: 0.8rem;
  color: var(--ink-muted);
  font-family: var(--sans);
  letter-spacing: 0.05em;
}

/* Theme rows */
.theme-row {
  display: flex;
  align-items: center;
  margin-bottom: 0.5rem;
  text-decoration: none;
  color: inherit;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--border);
  transition: background 0.2s;
}
.theme-row:hover { background: var(--bg-warm); }

.theme-label {
  width: 14rem;
  flex-shrink: 0;
  padding-right: 1rem;
}
.theme-dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-right: 0.5rem;
  vertical-align: middle;
}
.theme-name {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 0.9rem;
  vertical-align: middle;
}
.theme-subtitle {
  display: block;
  font-size: 0.75rem;
  color: var(--ink-muted);
  margin-top: 0.1rem;
}

.theme-track {
  position: relative;
  flex: 1;
  height: 2.5rem;
}

.theme-track svg.theme-line {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
}

.node-dot {
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 8px;
  height: 8px;
  border-radius: 50%;
  cursor: pointer;
  z-index: 2;
  transition: transform 0.2s;
}
.node-dot:hover {
  transform: translate(-50%, -50%) scale(2);
  z-index: 10;
}

.node-tooltip {
  display: none;
  position: absolute;
  bottom: 1.4rem;
  left: 50%;
  transform: translateX(-50%);
  background: var(--ink);
  color: #fff;
  padding: 0.4rem 0.8rem;
  border-radius: 4px;
  white-space: nowrap;
  font-family: var(--sans);
  font-size: 0.75rem;
  pointer-events: none;
}
.node-dot:hover .node-tooltip { display: block; }
.node-tooltip strong { display: block; font-weight: 500; }
.node-tooltip em { font-size: 0.7rem; opacity: 0.7; }

/* ── Theme Timeline View ── */
.theme-timeline-view {
  padding: 2rem 2rem 4rem;
  max-width: 56rem;
  margin: 0 auto;
}

.timeline-scroll {
  overflow-x: auto;
  padding: 2rem 0;
  -webkit-overflow-scrolling: touch;
}
.timeline-track {
  position: relative;
  min-width: 60rem;
  height: 16rem;
}

.timeline-node {
  position: absolute;
  top: 2rem;
  cursor: pointer;
}
.timeline-node .node-marker {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  position: relative;
  z-index: 2;
  border: 2px solid var(--bg);
  transition: transform 0.2s;
}
.timeline-node:hover .node-marker,
.timeline-node.active .node-marker {
  transform: scale(1.4);
  box-shadow: 0 0 0 4px rgba(139, 69, 19, 0.15);
}

.node-card {
  position: absolute;
  left: 1rem;
  top: -0.5rem;
  width: 16rem;
  padding: 0.8rem 1rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
  font-size: 0.85rem;
}
.timeline-node:hover .node-card,
.timeline-node.active .node-card {
  opacity: 1;
  pointer-events: auto;
}
.node-card .node-year {
  font-size: 0.7rem;
  color: var(--ink-muted);
  font-family: var(--sans);
}
.node-card h3 {
  font-family: var(--sans);
  font-size: 0.9rem;
  font-weight: 600;
  margin: 0.2rem 0;
}
.node-card p {
  color: var(--ink-light);
  font-size: 0.8rem;
  line-height: 1.5;
}
.read-link {
  display: inline-block;
  margin-top: 0.4rem;
  font-size: 0.8rem;
  color: var(--accent);
  text-decoration: none;
  font-family: var(--sans);
  font-weight: 500;
}

.timeline-line {
  position: absolute;
  top: 2.5rem; left: 0;
  width: 100%;
  height: 4px;
}

/* Node preview */
.node-preview {
  padding: 2rem;
  text-align: center;
  min-height: 6rem;
  transition: all 0.3s;
}
.node-preview .hint {
  color: var(--ink-muted);
  font-style: italic;
  font-size: 0.9rem;
}
.node-preview.active { background: var(--bg-warm); }
.node-preview.active h2 {
  font-family: var(--sans);
  font-size: 1.3rem;
  margin-bottom: 0.3rem;
}
.node-preview .year-tag {
  font-size: 0.8rem;
  color: var(--ink-muted);
  font-family: var(--sans);
}

/* ── Node Article ── */
.node-article {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 4rem 2rem 6rem;
}

.article-header {
  margin-bottom: 3rem;
  text-align: center;
}
.article-header h1 {
  font-family: var(--sans);
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  margin: 1rem 0 0.5rem;
}
.article-meta {
  color: var(--ink-muted);
  font-size: 0.9rem;
  font-family: var(--sans);
}

/* Article body — clean, readable, no section headers */
.article-body {
  font-size: 1.05rem;
  line-height: 1.9;
  color: var(--ink);
}
.article-body p {
  margin-bottom: 1.4rem;
}
.article-body h2 {
  font-family: var(--sans);
  font-size: 1.25rem;
  font-weight: 600;
  margin: 2.5rem 0 1rem;
  color: var(--ink);
}
.article-body h3 {
  font-family: var(--sans);
  font-size: 1.05rem;
  font-weight: 600;
  margin: 2rem 0 0.8rem;
}
.article-body blockquote {
  margin: 1.5rem 0;
  padding: 0.5rem 1.5rem;
  border-left: 3px solid var(--accent);
  font-style: italic;
  color: var(--ink-light);
  background: var(--bg-warm);
}
.article-body strong { font-weight: 700; color: var(--ink); }
.article-body em { font-style: italic; }
.article-body ul, .article-body ol {
  margin: 1rem 0 1.5rem 1.5rem;
}
.article-body li { margin-bottom: 0.5rem; }

/* Cross references */
.cross-refs {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}
.cross-refs h2 {
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink-muted);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.cross-refs li {
  list-style: none;
  margin-bottom: 0.5rem;
}
.cross-refs a {
  text-decoration: none;
  color: var(--ink);
  font-family: var(--serif);
  display: block;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border);
  transition: color 0.2s;
}
.cross-refs a:hover { color: var(--accent); }
.ref-theme {
  font-size: 0.8rem;
  font-family: var(--sans);
  font-weight: 600;
  margin-right: 0.6rem;
}
.ref-title { font-size: 0.95rem; }

/* Node nav footer */
.node-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  font-family: var(--sans);
  font-size: 0.9rem;
}
.node-nav a {
  text-decoration: none;
  color: var(--ink-light);
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.1rem;
  transition: color 0.2s, border-color 0.2s;
}
.node-nav a:hover { color: var(--ink); border-color: var(--ink); }
.node-nav .nav-theme {
  color: var(--accent);
  font-weight: 500;
}

/* Bottom nav */
.bottom-nav {
  text-align: center;
  padding: 2rem;
  font-family: var(--sans);
}
.bottom-nav a {
  color: var(--accent);
  text-decoration: none;
  font-size: 0.9rem;
}
.bottom-nav a:hover { text-decoration: underline; }

/* Footer */
.atlas-footer {
  text-align: center;
  padding: 3rem;
  color: var(--ink-muted);
  font-size: 0.8rem;
  border-top: 1px solid var(--border);
}

/* ── Responsive ── */
@media (max-width: 768px) {
  html { font-size: 16px; }
  .theme-row { flex-direction: column; align-items: flex-start; }
  .theme-label { width: 100%; margin-bottom: 0.5rem; }
  .theme-track { width: 100%; height: 3rem; }
  .timeline-track { min-width: 40rem; }
  .node-card { width: 12rem; font-size: 0.75rem; }
  .node-article { padding: 2rem 1rem 4rem; }
  .article-header h1 { font-size: 1.5rem; }
}
/* ── Theme vertical timeline (left-axis) ── */
.theme-timeline {
  max-width: 44rem;
  margin: 2rem auto 4rem;
  padding: 0 1.5rem;
}

.tl-row {
  display: grid;
  grid-template-columns: 4.5rem 1.5rem 1fr;
  align-items: start;
  gap: 0;
  margin-bottom: 1.2rem;
  min-height: 3rem;
}

.tl-gutter {
  text-align: right;
  padding-top: 0.35rem;
}
.tl-dynasty {
  display: inline-block;
  font-family: var(--sans);
  font-size: 0.7rem;
  font-weight: 600;
  color: #fff;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  letter-spacing: 0.05em;
}

.tl-line-col {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100%;
}
.tl-line-col::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: -1.2rem;
  left: 50%;
  width: 1px;
  background: var(--border);
}
.tl-row:last-child .tl-line-col::before {
  bottom: 50%;
}

.tl-marker {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid;
  background: var(--bg);
  z-index: 1;
  margin-top: 0.55rem;
  flex-shrink: 0;
}

.tl-card {
  padding: 0.6rem 0 0.6rem 1.2rem;
}
.tl-link {
  text-decoration: none;
  color: var(--ink);
  display: block;
}
.tl-link:hover h2 { color: var(--accent); }
.tl-year {
  font-family: var(--sans);
  font-size: 0.75rem;
  color: var(--ink-muted);
  margin-bottom: 0.2rem;
  display: block;
}
.tl-card h2 {
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 600;
  line-height: 1.4;
  transition: color 0.2s;
}

@media (max-width: 768px) {
  .tl-row {
    grid-template-columns: 3.2rem 1.5rem 1fr;
  }
  .tl-dynasty { font-size: 0.65rem; padding: 0.1rem 0.4rem; }
  .tl-card h2 { font-size: 0.95rem; }
}