/* ===================================================
   timeline.css — Interactive Timeline Tool Styles
   Inherits design tokens from styles.css
   =================================================== */

/* ===== Hero ===== */
.tl-hero {
  background: linear-gradient(135deg, #0a0a1a 0%, #1a1a3a 40%, #0a2a1a 100%);
}

.tl-hero::before {
  background:
    radial-gradient(circle at 20% 50%, rgba(212,168,67,0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 30%, rgba(41,128,185,0.1) 0%, transparent 40%);
}

.tl-hero .subtitle { color: #8ab0d0; }

/* ===== Section Spacing ===== */
.tl-section { padding: 4rem 0; }

/* ===== Timeline Tool Section ===== */
.tl-tool-section {
  background: var(--color-bg);
  min-height: 500px;
}

/* ===== Control Panel ===== */
.tl-controls {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 1.2rem 0;
  position: sticky;
  top: 56px;
  z-index: 800;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.controls-inner {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.filters-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.2rem;
  align-items: flex-end;
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.filter-group label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-secondary);
}

.filter-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
}

.pill {
  padding: 0.35rem 0.7rem;
  border: 1px solid var(--color-border);
  border-radius: 20px;
  font-size: 0.78rem;
  font-weight: 500;
  background: var(--color-bg);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.pill:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.pill.active {
  background: var(--color-ink);
  color: #fff;
  border-color: var(--color-ink);
}

.filter-search {
  flex: 1;
  min-width: 180px;
}

.filter-search input {
  padding: 0.45rem 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: 0.85rem;
  background: var(--color-bg);
  color: var(--color-text);
  width: 100%;
  transition: border-color var(--transition);
}

.filter-search input:focus {
  outline: none;
  border-color: var(--color-accent);
}

.controls-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.view-toggles {
  display: flex;
  gap: 0.3rem;
}

.view-btn {
  width: 36px;
  height: 36px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-bg);
  font-size: 1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
  color: var(--color-text-secondary);
}

.view-btn:hover { border-color: var(--color-accent); color: var(--color-accent); }
.view-btn.active { background: var(--color-ink); color: #fff; border-color: var(--color-ink); }

.tl-stats {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.tl-stats strong { color: var(--color-accent); }

/* ===== Horizontal Timeline ===== */
.tl-horizontal {
  padding: 2rem 0;
}

.dynasty-band {
  position: relative;
  height: 32px;
  margin-bottom: 0.5rem;
  overflow: hidden;
  border-radius: 6px;
}

.dynasty-segment {
  position: absolute;
  top: 0;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 600;
  color: rgba(255,255,255,0.85);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  padding: 0 0.5rem;
}

.tl-scroll-wrapper {
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  padding: 2rem 0;
  cursor: grab;
}

.tl-scroll-wrapper:active { cursor: grabbing; }

.tl-scroll-wrapper::-webkit-scrollbar { height: 8px; }
.tl-scroll-wrapper::-webkit-scrollbar-track { background: var(--color-bg); border-radius: 4px; }
.tl-scroll-wrapper::-webkit-scrollbar-thumb { background: var(--color-border); border-radius: 4px; }

.tl-track {
  position: relative;
  height: 120px;
  border-bottom: 3px solid var(--color-border);
}

.tl-node {
  position: absolute;
  bottom: -6px;
  transform: translateX(-50%);
  cursor: pointer;
  z-index: 2;
}

.node-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  margin: 0 auto 0.5rem;
  transition: all var(--transition);
  border: 2px solid var(--color-surface);
}

.tl-node:hover .node-dot {
  transform: scale(1.5);
}

.node-label {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  max-width: 100px;
  opacity: 0;
  transform: translateY(-5px);
  transition: all var(--transition);
  pointer-events: none;
}

.tl-node:hover .node-label {
  opacity: 1;
  transform: translateY(0);
}

.node-year {
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--color-accent);
}

.node-name {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-ink);
  line-height: 1.3;
}

.tl-scroll-hint {
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  opacity: 0.6;
  margin-top: 0.5rem;
}

/* ===== Vertical Timeline ===== */
.tl-vertical {
  padding: 3rem 0;
}

.tl-v-track {
  max-width: 700px;
  margin: 0 auto;
  position: relative;
  padding-left: 3rem;
}

.tl-v-track::before {
  content: '';
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--color-accent), var(--color-gold), var(--color-accent));
  border-radius: 2px;
}

.v-item {
  position: relative;
  margin-bottom: 2rem;
  cursor: pointer;
  transition: all var(--transition);
}

.v-item:hover { transform: translateX(4px); }

.v-marker {
  position: absolute;
  left: -2.55rem;
  top: 0.3rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 3px solid var(--color-bg);
  box-shadow: 0 0 0 3px var(--color-accent);
}

.v-content {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.2rem 1.5rem;
  box-shadow: var(--shadow);
  transition: box-shadow var(--transition);
}

.v-item:hover .v-content { box-shadow: var(--shadow-hover); }

.v-year {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-accent);
  font-size: 0.9rem;
  margin-bottom: 0.3rem;
}

.v-content h4 { font-size: 1.05rem; margin-bottom: 0.4rem; }
.v-cn { font-weight: 400; color: var(--color-text-secondary); font-size: 0.9rem; }
.v-content p { font-size: 0.9rem; color: var(--color-text-secondary); margin-bottom: 0.5rem; line-height: 1.6; }
.v-dynasty {
  display: inline-block;
  background: var(--color-gold-light);
  padding: 0.15rem 0.6rem;
  border-radius: 10px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-gold);
}

/* ===== Grid View ===== */
.tl-grid-view { padding: 3rem 0; }

.grid-group {
  margin-bottom: 3rem;
}

.grid-group-title {
  font-size: 1.3rem;
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.grid-count {
  font-size: 0.8rem;
  background: var(--color-gold-light);
  padding: 0.1rem 0.5rem;
  border-radius: 10px;
  color: var(--color-gold);
}

.grid-items {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.2rem;
}

.grid-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.2rem;
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: all var(--transition);
  border-top: 3px solid;
}

.grid-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.gc-year {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--color-accent);
  margin-bottom: 0.3rem;
}

.grid-card h4 { font-size: 1rem; margin-bottom: 0.2rem; }
.gc-cn { font-size: 0.8rem; color: var(--color-text-secondary); margin-bottom: 0.5rem; }
.gc-summary { font-size: 0.82rem; color: var(--color-text-secondary); line-height: 1.5; margin: 0; }

/* ===== Modal ===== */
.tl-modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  backdrop-filter: blur(4px);
}

.tl-modal {
  background: var(--color-surface);
  border-radius: var(--radius);
  max-width: 600px;
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
  position: relative;
}

.modal-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 32px;
  height: 32px;
  border: none;
  background: rgba(255,255,255,0.2);
  color: #fff;
  border-radius: 50%;
  font-size: 1rem;
  cursor: pointer;
  z-index: 3;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition);
}

.modal-close:hover { background: rgba(255,255,255,0.3); }

.modal-header {
  padding: 2rem 2rem 1.5rem;
  border-radius: var(--radius) var(--radius) 0 0;
  color: #fff;
}

.modal-cat {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  opacity: 0.8;
}

.modal-header h2 { color: #fff; margin: 0.3rem 0 0.2rem; font-size: 1.5rem; }
.modal-cn { font-size: 1.1rem; opacity: 0.8; margin: 0; }

.modal-body { padding: 1.5rem 2rem 2rem; }

.modal-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.2rem;
}

.meta-tag {
  background: var(--color-bg);
  padding: 0.3rem 0.7rem;
  border-radius: 15px;
  font-size: 0.8rem;
  font-weight: 500;
}

.modal-summary {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
}

.modal-body h4 { font-size: 1rem; margin-bottom: 0.8rem; }

.modal-facts {
  list-style: none;
  padding: 0;
  margin-bottom: 1.5rem;
}

.modal-facts li {
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.93rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.modal-facts li:last-child { border-bottom: none; }

.modal-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--color-accent);
  color: #fff;
  padding: 0.6rem 1.5rem;
  border-radius: 25px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition);
  margin-bottom: 1.5rem;
}

.modal-link:hover { background: var(--color-accent-dark); color: #fff; }

.modal-related h4 { margin-bottom: 0.8rem; }

.related-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.related-tag {
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--color-border);
  border-radius: 15px;
  font-size: 0.78rem;
  background: var(--color-bg);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.related-tag:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== Guided Stories ===== */
.stories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  max-width: 960px;
  margin: 0 auto;
}

.story-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: all var(--transition);
  border: 2px solid transparent;
  font-family: inherit;
  color: inherit;
}

.story-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--color-gold);
}

.story-icon { font-size: 2.5rem; margin-bottom: 0.8rem; }
.story-card h3 { font-size: 1.05rem; margin-bottom: 0.5rem; }
.story-card p { font-size: 0.85rem; color: var(--color-text-secondary); margin: 0; line-height: 1.6; }

/* ===== Compare Section ===== */
.compare-section {
  background: var(--color-surface);
}

.compare-grid {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.compare-pair {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  align-items: stretch;
}

.compare-china,
.compare-world {
  background: var(--color-bg);
  border-radius: var(--radius);
  padding: 1.2rem 1.5rem;
  box-shadow: var(--shadow);
}

.compare-china { border-left: 4px solid var(--color-accent); }
.compare-world { border-left: 4px solid #5a7a9a; }

.compare-year {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--color-accent);
}

.compare-china h4,
.compare-world h4 { font-size: 1rem; margin: 0.3rem 0 0.4rem; }

.compare-china p,
.compare-world p { font-size: 0.88rem; color: var(--color-text-secondary); margin: 0; line-height: 1.6; }

.compare-vs {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-gold);
  align-self: center;
}

/* ===== Download Section ===== */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  max-width: 800px;
  margin: 0 auto;
}

.download-card {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  box-shadow: var(--shadow);
}

.dl-icon { font-size: 2.5rem; margin-bottom: 0.8rem; }
.download-card h4 { font-size: 1.05rem; margin-bottom: 0.5rem; }
.download-card p { font-size: 0.88rem; color: var(--color-text-secondary); margin-bottom: 1rem; line-height: 1.6; }

.dl-btn {
  background: var(--color-ink);
  color: #fff;
  border: none;
  padding: 0.5rem 1.2rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
}

.dl-btn:hover { background: var(--color-accent); }

.citation-box {
  max-width: 800px;
  margin: 2rem auto 0;
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
}

.citation-box h4 { margin-bottom: 1.2rem; }

.citation-format { margin-bottom: 1.2rem; }
.citation-format:last-child { margin-bottom: 0; }
.citation-format h5 { font-size: 0.9rem; margin-bottom: 0.4rem; color: var(--color-accent); }
.citation-text { font-size: 0.88rem; color: var(--color-text-secondary); background: var(--color-bg); padding: 0.8rem; border-radius: 8px; line-height: 1.6; }

/* ===== Hidden Utility ===== */
.hidden { display: none !important; }

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .compare-pair {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
  .compare-vs { text-align: center; }
}

@media (max-width: 768px) {
  .filters-row {
    flex-direction: column;
    gap: 0.8rem;
  }

  .filter-group { width: 100%; }
  .filter-pills { overflow-x: auto; flex-wrap: nowrap; -webkit-overflow-scrolling: touch; padding-bottom: 0.3rem; }

  .controls-bottom {
    flex-direction: column;
    gap: 0.5rem;
    align-items: flex-start;
  }

  .stories-grid { grid-template-columns: 1fr 1fr; }
  .download-grid { grid-template-columns: 1fr; }
  .grid-items { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .stories-grid { grid-template-columns: 1fr; }
  .tl-modal-overlay { padding: 1rem; }
  .modal-body { padding: 1rem 1.5rem 1.5rem; }
}

/* ===== Dark Mode ===== */
@media (prefers-color-scheme: dark) {
  .tl-hero { background: linear-gradient(135deg, #04040a 0%, #0a0a1a 40%, #040a04 100%); }
  .pill.active { background: var(--color-ink); }
  .view-btn.active { background: var(--color-ink); }
  .v-content { background: var(--color-surface); }
  .grid-card { background: var(--color-surface); }
  .compare-china, .compare-world { background: var(--color-surface); }
  .download-card { background: var(--color-surface); }
  .citation-box { background: var(--color-surface); }
  .modal-close { background: rgba(0,0,0,0.3); }
}

/* ===== Print ===== */
@media print {
  .tl-controls,
  .view-toggles,
  .stories-grid,
  .download-grid,
  .tl-scroll-hint { display: none; }
  .tl-horizontal { display: none; }
  .tl-vertical { display: block !important; }
}