:root {
  --bg-deep: #d5dce3;
  --bg-panel: rgba(248, 250, 252, 0.82);
  --ink: #1a1d24;
  --ink-soft: #4a5160;
  --crimson: #8f1d2c;
  --crimson-deep: #6b1521;
  --bronze: #9a7b3c;
  --bronze-soft: #c4a574;
  --sea: #3d6b7a;
  --sea-deep: #2a4f5c;
  --land: #b8c0b0;
  --land-edge: #8a9480;
  --empire: #b8454a;
  --empire-fill: rgba(184, 69, 74, 0.55);
  --neighbor-fill: rgba(90, 110, 100, 0.28);
  --line: rgba(26, 29, 36, 0.14);
  --shadow: 0 18px 48px rgba(26, 40, 55, 0.12);
  --font-display: "Cinzel", "Noto Serif SC", serif;
  --font-body: "Noto Serif SC", "Songti SC", serif;
  --radius: 2px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  color: var(--ink);
  font-family: var(--font-body);
  background: var(--bg-deep);
  overflow-x: hidden;
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-height: 100vh;
}

.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse 80% 50% at 15% 10%, rgba(61, 107, 122, 0.18), transparent 55%),
    radial-gradient(ellipse 70% 45% at 90% 80%, rgba(143, 29, 44, 0.1), transparent 50%),
    linear-gradient(165deg, #e8eef2 0%, #d2dae3 42%, #c5cfd8 100%);
  pointer-events: none;
}

.atmosphere::after {
  content: "";
  position: absolute;
  inset: 0;
  opacity: 0.35;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.45'/%3E%3C/svg%3E");
  mix-blend-mode: multiply;
}

/* —— Brand —— */
.site-brand {
  padding: 1.1rem 1.5rem 0.4rem;
  text-align: center;
  animation: rise-in 0.9s ease both;
}

.brand-latin {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 3.2vw, 2.15rem);
  font-weight: 700;
  letter-spacing: 0.28em;
  color: var(--crimson);
  text-indent: 0.28em;
}

.brand-zh {
  margin: 0.15rem 0 0;
  font-size: clamp(0.85rem, 1.5vw, 1.05rem);
  font-weight: 600;
  letter-spacing: 0.45em;
  color: var(--ink-soft);
  text-indent: 0.45em;
}

/* —— Stage：三栏 —— */
.stage {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(240px, 0.85fr) minmax(240px, 0.85fr);
  gap: 0.75rem;
  padding: 0.5rem 1rem 0.4rem;
  min-height: 0;
  animation: rise-in 1s 0.12s ease both;
  align-items: stretch;
}

.stage:has(#panelMap.is-collapsed) {
  grid-template-columns: auto minmax(240px, 1fr) minmax(240px, 1fr);
}

.stage:has(#panelRome.is-collapsed):has(#panelChurch:not(.is-collapsed)) {
  /* keep readable */
}

.panel {
  background: var(--bg-panel);
  backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  min-height: 0;
  display: flex;
  flex-direction: column;
  transition: flex 0.25s ease, min-width 0.25s ease;
}

.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.55rem 0.75rem;
  border-bottom: 1px solid var(--line);
  flex-shrink: 0;
}

.panel-kicker {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  color: var(--bronze);
  font-family: var(--font-display);
}

.panel-name {
  display: block;
  margin-top: 0.1rem;
  font-size: 0.95rem;
  color: var(--crimson-deep);
  letter-spacing: 0.04em;
}

.panel-toggle {
  appearance: none;
  border: 1px solid var(--line);
  background: rgba(248, 250, 252, 0.9);
  color: var(--ink-soft);
  font-family: var(--font-body);
  font-size: 0.72rem;
  padding: 0.28rem 0.55rem;
  cursor: pointer;
  letter-spacing: 0.06em;
}

.panel-toggle:hover {
  color: var(--crimson);
  border-color: rgba(143, 29, 44, 0.35);
}

.panel-body {
  flex: 1;
  min-height: 0;
  overflow: auto;
  padding: 0.65rem 0.85rem 0.9rem;
}

.panel.is-collapsed {
  min-width: 2.6rem;
  max-width: 2.6rem;
}

.panel.is-collapsed .panel-head {
  flex-direction: column;
  align-items: stretch;
  height: 100%;
  border-bottom: 0;
  padding: 0.5rem 0.25rem;
}

.panel.is-collapsed .panel-head-text {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  margin: 0 auto;
  letter-spacing: 0.12em;
}

.panel.is-collapsed .panel-kicker {
  display: none;
}

.panel.is-collapsed .panel-name {
  font-size: 0.82rem;
}

.panel.is-collapsed .panel-toggle {
  margin-top: auto;
  width: 100%;
  padding: 0.35rem 0;
}

.panel.is-collapsed .panel-body {
  display: none;
}

.map-panel .panel-body {
  display: flex;
  flex-direction: column;
  padding-bottom: 0.75rem;
}

.map-panel.is-collapsed .panel-body {
  display: none;
}

.map-panel {
  /* panel base already applied */
}

.map-chrome {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem 1rem;
  margin-bottom: 0.55rem;
  padding: 0 0.2rem;
}

.map-year {
  font-family: var(--font-display);
  font-size: 1.05rem;
  letter-spacing: 0.08em;
  color: var(--crimson-deep);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

.map-year.is-shifting {
  opacity: 0;
  transform: translateY(-4px);
}

.map-legend {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 0.65rem;
  font-size: 0.72rem;
  color: var(--ink-soft);
  max-width: 100%;
}

.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
  white-space: nowrap;
}

.swatch {
  display: inline-block;
  width: 0.85rem;
  height: 0.55rem;
  margin-right: 0.1rem;
  border: 1px solid transparent;
}

.swatch.empire {
  background: var(--empire-fill);
  border-color: var(--empire);
}

.swatch.neighbor {
  background: var(--neighbor-fill);
  border-color: var(--land-edge);
}

.polity-poly {
  stroke-linejoin: round;
}

.map-credit {
  margin: 0 0 0.45rem;
  padding: 0 0.2rem;
  font-size: 0.68rem;
  color: var(--ink-soft);
  opacity: 0.8;
  letter-spacing: 0.04em;
}

.swatch {
  display: inline-block;
  width: 0.85rem;
  height: 0.55rem;
  margin-right: 0.15rem;
}

.swatch.empire {
  background: var(--empire-fill);
  border: 1px solid var(--empire);
}

.swatch.neighbor {
  background: var(--neighbor-fill);
  border: 1px solid var(--land-edge);
}

.map-frame {
  flex: 1;
  min-height: 360px;
  height: 100%;
  position: relative;
  background: #d9e2e8;
  border: 1px solid var(--line);
  overflow: hidden;
}

.leaflet-host {
  width: 100%;
  height: 100%;
  min-height: 360px;
}

.leaflet-container {
  width: 100%;
  height: 100%;
  min-height: 360px;
  font-family: var(--font-body);
  background: #c5d4dc;
}

.map-capital-tip {
  background: rgba(248, 250, 252, 0.92);
  border: 1px solid var(--crimson);
  color: var(--crimson-deep);
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 700;
  padding: 2px 6px;
  border-radius: 2px;
  box-shadow: none;
}

.map-capital-tip::before {
  border-right-color: var(--crimson);
}

.neighbor-label span,
.empire-title-label span {
  display: inline-block;
  white-space: nowrap;
  pointer-events: none;
}

.neighbor-label span {
  transform: translate(-50%, -50%);
  padding: 2px 7px;
  font-size: 11px;
  color: var(--ink-soft);
  background: rgba(248, 250, 252, 0.82);
  border: 1px dashed var(--land-edge);
}

.empire-title-label span {
  transform: translate(-50%, 0);
  padding: 3px 8px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--crimson-deep);
  background: rgba(248, 250, 252, 0.88);
  border: 1px solid var(--empire);
}

.empire-poly {
  stroke-linejoin: round;
  stroke-linecap: round;
}

.empire-outline {
  pointer-events: none;
}

.leaflet-overlay-pane svg path.empire-poly {
  paint-order: stroke fill;
}

/* —— Info —— */
.info-panel .panel-body,
.church-panel .panel-body {
  max-height: calc(100vh - 14rem);
}

.church-inactive {
  padding: 0.75rem 0.2rem 1rem;
}

.church-inactive-title {
  margin: 0 0 0.45rem;
  font-size: 1rem;
  color: var(--ink-soft);
  letter-spacing: 0.06em;
}

.church-inactive-text {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--ink-soft);
  opacity: 0.9;
}

.church-panel.is-pre-church .church-timeline-block,
body.is-pre-church .church-timeline-block {
  opacity: 0.55;
}

.church-eras {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  margin-bottom: 0.65rem;
}

.church-eras button {
  appearance: none;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink-soft);
  font-family: var(--font-body);
  font-size: 0.68rem;
  padding: 0.22rem 0.4rem;
  cursor: pointer;
  letter-spacing: 0.04em;
}

.church-eras button.is-active {
  color: var(--crimson-deep);
  border-color: rgba(143, 29, 44, 0.45);
  background: rgba(143, 29, 44, 0.06);
  font-weight: 700;
}

.church-range {
  margin: 0 0 0.45rem;
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--sea-deep);
}

.period-era {
  margin: 0;
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--bronze);
  text-transform: uppercase;
}

.period-summary {
  margin: 0 0 0.9rem;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

.meta-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.55rem;
  margin: 0 0 1rem;
  padding: 0.7rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.meta-grid dt {
  margin: 0;
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--bronze);
}

.meta-grid dd {
  margin: 0.2rem 0 0;
  font-size: 0.86rem;
  font-weight: 600;
  line-height: 1.35;
}

.info-block {
  margin-bottom: 0.85rem;
}

.info-block h3 {
  margin: 0 0 0.3rem;
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--crimson);
  font-weight: 700;
}

.info-block p,
.info-block li {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

.info-block ul {
  margin: 0;
  padding-left: 1.1rem;
}

.info-block li + li {
  margin-top: 0.25rem;
}

.period-timeline {
  list-style: none;
  margin: 0.15rem 0 0;
  padding: 0;
  border-left: 2px solid rgba(143, 29, 44, 0.28);
}

.period-timeline li {
  position: relative;
  display: grid;
  grid-template-columns: 6.2rem 1fr;
  gap: 0.45rem 0.7rem;
  padding: 0.35rem 0 0.55rem 0.95rem;
  font-size: 0.84rem;
  line-height: 1.55;
  color: var(--ink-soft);
}

.period-timeline li::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 0.7rem;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--crimson);
  border: 2px solid #f8fafc;
}

.period-timeline time {
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--crimson-deep);
  font-weight: 700;
  line-height: 1.4;
  padding-top: 0.12rem;
}

.period-timeline span {
  min-width: 0;
}

.church-timeline li {
  grid-template-columns: 7.2rem 1fr;
}

.period-timeline .timeline-empty {
  display: block;
  padding-left: 0.95rem;
  border: 0;
  color: var(--ink-soft);
  opacity: 0.7;
}

.period-timeline .timeline-empty::before {
  display: none;
}

@media (max-width: 560px) {
  .period-timeline li {
    grid-template-columns: 1fr;
    gap: 0.15rem;
  }
}

.info-panel.is-shifting .period-title,
.info-panel.is-shifting .period-summary,
.info-panel.is-shifting .meta-grid,
.info-panel.is-shifting .info-block {
  opacity: 0;
  transform: translateY(6px);
}

.info-panel .period-title,
.info-panel .period-summary,
.info-panel .meta-grid,
.info-panel .info-block {
  transition: opacity 0.35s ease, transform 0.35s ease;
}

/* —— Timeline —— */
.timeline {
  padding: 0.45rem 1.25rem 0.85rem;
  animation: rise-in 1s 0.22s ease both;
}

.timeline-block + .timeline-block {
  margin-top: 0.45rem;
  padding-top: 0.4rem;
  border-top: 1px solid var(--line);
}

.timeline-caption {
  margin: 0 0 0.25rem;
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--bronze);
  font-family: var(--font-display);
}

.timeline-labels {
  display: flex;
  justify-content: space-between;
  gap: 0.25rem;
  margin-bottom: 0.35rem;
  padding: 0 0.35rem;
}

.timeline-labels button {
  appearance: none;
  border: 0;
  background: transparent;
  padding: 0.15rem 0.15rem;
  font-family: var(--font-body);
  font-size: clamp(0.52rem, 0.95vw, 0.68rem);
  color: var(--ink-soft);
  cursor: pointer;
  flex: 1;
  min-width: 0;
  text-align: center;
  line-height: 1.25;
  transition: color 0.25s ease;
}

.timeline-labels button:hover,
.timeline-labels button.is-active {
  color: var(--crimson);
  font-weight: 700;
}

.timeline-track-wrap {
  position: relative;
  padding: 0.35rem 0 0.5rem;
}

.timeline-slider.church-slider {
  background: linear-gradient(90deg, var(--bronze-soft), var(--sea), var(--crimson));
}

.timeline-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #f8fafc;
  border: 3px solid var(--crimson);
  box-shadow: 0 2px 8px rgba(26, 40, 55, 0.2);
  cursor: grab;
  transition: transform 0.2s ease;
}

.timeline-slider::-webkit-slider-thumb:active {
  cursor: grabbing;
  transform: scale(1.08);
}

.timeline-slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #f8fafc;
  border: 3px solid var(--crimson);
  box-shadow: 0 2px 8px rgba(26, 40, 55, 0.2);
  cursor: grab;
}

.timeline-ticks {
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  justify-content: space-between;
  pointer-events: none;
  z-index: 1;
  padding: 0 7px;
}

.timeline-ticks span {
  width: 2px;
  height: 12px;
  background: rgba(26, 29, 36, 0.28);
}

.timeline-hint {
  margin: 0.35rem 0 0;
  text-align: center;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
  opacity: 0.85;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 1100px) {
  .stage {
    grid-template-columns: 1fr 1fr;
  }

  .map-panel {
    grid-column: 1 / -1;
  }

  .panel.is-collapsed {
    min-width: 0;
    max-width: none;
  }

  .panel.is-collapsed .panel-head {
    flex-direction: row;
    height: auto;
  }

  .panel.is-collapsed .panel-head-text {
    writing-mode: horizontal-tb;
  }
}

@media (max-width: 960px) {
  body {
    grid-template-rows: auto auto auto;
  }

  .stage {
    grid-template-columns: 1fr;
    padding: 0.4rem 0.85rem;
  }

  .map-frame {
    min-height: 280px;
    aspect-ratio: 16 / 10;
  }

  .info-panel .panel-body,
  .church-panel .panel-body {
    max-height: none;
  }

  .meta-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }

  .timeline-labels {
    overflow-x: auto;
    justify-content: flex-start;
  }

  .timeline-labels button {
    flex: 0 0 auto;
    max-width: 5.5rem;
  }
}

@media (max-width: 560px) {
  .brand-latin {
    letter-spacing: 0.14em;
    text-indent: 0.14em;
  }

  .meta-grid {
    grid-template-columns: 1fr;
  }

  .map-legend {
    font-size: 0.7rem;
  }
}