/* ==========================================================================
   MAKE AI BETTER — History of Computing Stylesheet (Motion.dev & Timeline)
   ========================================================================== */

.history-body {
  background: radial-gradient(circle at 50% 0%, #0d1124 0%, #06070b 50%, #040508 100%);
  color: var(--text-primary);
  position: relative;
  overflow-x: hidden;
}

/* Ambient Glows for History */
.history-glow-1 {
  top: 100px;
  left: -200px;
  background: radial-gradient(circle, rgba(255, 183, 3, 0.12), transparent 70%);
}
.history-glow-2 {
  top: 1800px;
  right: -200px;
  background: radial-gradient(circle, rgba(138, 43, 226, 0.15), transparent 70%);
}
.history-glow-3 {
  bottom: 800px;
  left: 50%;
  transform: translateX(-50%);
  background: radial-gradient(circle, rgba(0, 240, 255, 0.18), transparent 70%);
}

/* Scroll Progress Bar at Top */
.scroll-progress-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.05);
}
.scroll-progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #ffb703, #8a2be2, #00f0ff, #00ff88);
  box-shadow: 0 0 10px rgba(0, 240, 255, 0.8);
  transition: width 0.1s linear;
}

/* Barra de Cronologia Horizontal (topo) */
.timeline-scrubber {
  position: fixed;
  top: 84px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 90;
  display: flex;
  align-items: center;
  gap: 0.9rem;
  max-width: calc(100vw - 2rem);
  background: rgba(13, 16, 28, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  padding: 0.5rem 0.85rem;
  border-radius: 40px;
  border: 1px solid var(--border-subtle);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.55);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-smooth), transform var(--transition-smooth);
}
.timeline-scrubber.is-visible {
  opacity: 1;
  pointer-events: auto;
}
.scrubber-label {
  font-family: var(--font-mono);
  font-size: 0.55rem;
  color: var(--text-muted);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  white-space: nowrap;
}
.scrubber-track {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  position: relative;
}
/* fio que liga os anos */
.scrubber-track::before {
  content: '';
  position: absolute;
  left: 14px;
  right: 14px;
  top: 50%;
  height: 1px;
  background: linear-gradient(90deg, rgba(255, 183, 3, 0.45), rgba(138, 43, 226, 0.5), rgba(0, 240, 255, 0.6), rgba(0, 255, 136, 0.7));
  z-index: 0;
}
.scrub-dot {
  position: relative;
  z-index: 1;
  min-width: 52px;
  height: 28px;
  padding: 0 0.55rem;
  border-radius: 999px;
  background: rgba(10, 13, 24, 0.95);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  transition: all var(--transition-fast);
}
.scrub-dot:hover {
  color: #ffffff;
  border-color: var(--accent-cyan);
  background: rgba(0, 240, 255, 0.18);
  transform: translateY(-2px);
}
.scrub-dot.active {
  background: var(--accent-cyan);
  color: #050811;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 14px rgba(0, 240, 255, 0.7);
}
.scrubber-rail-progress {
  width: 70px;
  height: 3px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  overflow: hidden;
}
.scrubber-rail-progress span {
  display: block;
  height: 100%;
  width: 0%;
  border-radius: 999px;
  background: linear-gradient(90deg, #ffb703, #00f0ff);
  transition: width 0.15s linear;
}

/* Hero Section */
.history-hero {
  padding-top: 150px;
  padding-bottom: 90px;
  text-align: center;
  position: relative;
  z-index: 2;
}
.hero-container-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.history-title {
  font-size: 3.6rem;
  margin-bottom: 1.25rem;
  line-height: 1.15;
}
.history-subtitle-text {
  font-size: 1.8rem;
  font-weight: 600;
  color: #ffffff;
  display: block;
  margin-top: 0.4rem;
}
.history-lead {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.8;
  max-width: 820px;
  margin-bottom: 2.5rem;
}
.hero-action-row {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Trilho Horizontal — viewport, setas e faixa de painéis */
.timeline-viewport {
  position: relative;
  z-index: 2;
  /* espaço para a navbar fixa + a barra CRONOLOGIA flutuante */
  padding: 150px 0 70px;
}

.timeline-rail {
  display: flex;
  align-items: stretch;
  gap: 2.5rem;
  overflow-x: auto;
  overflow-y: hidden;
  scroll-snap-type: x mandatory;

  overscroll-behavior-x: contain;
  padding: 0 max(1.5rem, calc(50vw - 590px)) 1.5rem;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.timeline-rail::-webkit-scrollbar { display: none; }
.timeline-rail:focus-visible {
  outline: 2px solid var(--accent-cyan);
  outline-offset: -6px;
  border-radius: 24px;
}

/* Setas de navegação */
.rail-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 20;
  width: 54px;
  height: 54px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: #ffffff;
  background: rgba(13, 16, 28, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.55);
  transition: all var(--transition-fast);
}
.rail-nav:hover:not(:disabled) {
  border-color: var(--accent-cyan);
  background: rgba(0, 240, 255, 0.18);
  box-shadow: 0 0 24px rgba(0, 240, 255, 0.35);
}
.rail-nav:disabled {
  opacity: 0.22;
  cursor: default;
}
.rail-nav-prev { left: 1.1rem; }
.rail-nav-next { right: 1.1rem; }

.rail-hint {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  margin-top: 1.4rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  transition: opacity var(--transition-smooth);
}
.rail-hint.is-dismissed { opacity: 0; }

/* Painel de Era */
.epoch-section {
  position: relative;
  flex: 0 0 min(1180px, 92vw);
  scroll-snap-align: center;
  scroll-snap-stop: always;
  display: flex;
  flex-direction: column;
  align-items: stretch;
}

.epoch-marker {
  position: relative;
  z-index: 3;
  margin: 0 auto 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.marker-connector {
  width: 2px;
  height: 22px;
  background: linear-gradient(180deg, var(--accent-cyan), transparent);
}
.marker-circle {
  width: 70px;
  height: 70px;
  border-radius: 50%;
  background: #090c18;
  border: 2px solid var(--accent-cyan);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.05rem;
  color: #ffffff;
  letter-spacing: 0.05em;
}

/* Epoch Cards */
.epoch-card {
  width: 100%;
  flex: 1 1 auto;
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(280px, 370px) 1fr;
  grid-template-rows: auto minmax(0, 1fr);
  grid-template-areas:
    "head head"
    "visual body";
  column-gap: 2.5rem;
  max-height: min(70vh, 780px);
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  border-radius: 22px;
  padding: 2.4rem 2.6rem;
  box-shadow: var(--shadow-card);
  position: relative;
  z-index: 2;
  transition: border-color var(--transition-smooth), box-shadow var(--transition-smooth);
}
.epoch-card:hover {
  border-color: var(--border-light);
  box-shadow: var(--shadow-card), 0 0 35px rgba(0, 240, 255, 0.12);
}

.active-frontier-card {
  border: 1px solid rgba(0, 240, 255, 0.4);
  background: linear-gradient(135deg, rgba(14, 18, 33, 0.9) 0%, rgba(19, 24, 46, 0.9) 100%);
  box-shadow: var(--shadow-card), 0 0 45px rgba(0, 240, 255, 0.18);
}

.epoch-header {
  grid-area: head;
  margin-bottom: 1.6rem;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 1.5rem;
}
.epoch-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}
.epoch-quote {
  font-family: var(--font-heading);
  font-style: italic;
  font-size: 0.92rem;
  color: var(--text-muted);
}
.epoch-title {
  font-size: clamp(1.5rem, 2vw, 2.1rem);
  margin-top: 0.35rem;
  line-height: 1.25;
}
.epoch-body p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 1.4rem;
}
.epoch-body p strong {
  color: #ffffff;
}

/* Takeaways */
.epoch-takeaways {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
  margin-top: 2rem;
  border-top: 1px solid var(--border-subtle);
  padding-top: 1.5rem;
}
.takeaway-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: 0.88rem;
  color: var(--text-muted);
}
.takeaway-num {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--accent-cyan);
  font-size: 0.95rem;
}

/* Interactive Widgets Common Styling */
.interactive-widget-box {
  background: rgba(8, 10, 18, 0.8);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 1.8rem;
  margin: 2rem 0;
  box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5);
}
.widget-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}
.widget-title-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: #ffffff;
  font-size: 1.05rem;
}
.widget-controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.25rem;
}

/* Turing Machine Tape Widget */
.turing-tape-wrapper {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 1.5rem 0;
}
.turing-head-pointer {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 0.5rem;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.head-arrow {
  color: var(--accent-cyan);
  font-size: 1.4rem;
  line-height: 1;
}
.head-state-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: rgba(0, 240, 255, 0.15);
  color: var(--accent-cyan);
  border: 1px solid var(--accent-cyan);
  padding: 2px 8px;
  border-radius: 10px;
}
.turing-cells-row {
  display: flex;
  gap: 0.45rem;
  overflow-x: auto;
  max-width: 100%;
  padding: 0.5rem;
}
.turing-cell {
  width: 52px;
  height: 52px;
  background: #111526;
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 700;
  color: #ffffff;
  transition: all var(--transition-fast);
}
.turing-cell.active-cell {
  border-color: var(--accent-cyan);
  background: rgba(0, 240, 255, 0.18);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.4);
  color: var(--accent-cyan);
}
.turing-explanation {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-left: auto;
}

/* Transistor Comparison Grid */
.transistor-visualizer-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1.5rem;
}
.compare-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.4rem;
}
.valve-card { border-color: rgba(255, 183, 3, 0.3); }
.transistor-card { border-color: rgba(0, 255, 136, 0.4); }
.card-tag {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 1rem;
  color: #ffffff;
}
.compare-vs {
  font-family: var(--font-mono);
  font-weight: 800;
  color: var(--text-muted);
  font-size: 1.2rem;
}
.spec-row {
  display: flex;
  justify-content: space-between;
  font-size: 0.88rem;
  margin-bottom: 0.5rem;
}
.spec-row span { color: var(--text-muted); }
.spec-row strong { color: #ffffff; }

/* Moore's Law Slider */
.moore-slider-box {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.moore-slider-box input[type="range"] {
  width: 100%;
  accent-color: var(--accent-green);
  cursor: pointer;
}
.moore-display-readout {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  background: rgba(0, 0, 0, 0.4);
  border-radius: 10px;
  padding: 1rem;
  font-family: var(--font-mono);
  font-size: 0.95rem;
}
.readout-year { color: var(--accent-amber); font-weight: 700; }
.readout-chip { color: #ffffff; }
.readout-count { color: var(--accent-green); font-weight: 700; }

/* Backpropagation Canvas */
.backprop-interactive-canvas {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  align-items: center;
  background: rgba(0, 0, 0, 0.35);
  border-radius: 12px;
  padding: 1.5rem;
  gap: 1.5rem;
  margin-bottom: 1rem;
}
.nn-layer-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.85rem;
}
.layer-title {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
}
.node-circle {
  width: 58px;
  height: 58px;
  border-radius: 50%;
  background: #14182b;
  border: 2px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: #ffffff;
  box-shadow: 0 0 10px rgba(0, 240, 255, 0.25);
}
.output-node {
  border-color: var(--accent-purple);
  box-shadow: 0 0 10px rgba(138, 43, 226, 0.3);
}
.nn-weights-col {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-green);
}
.loss-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-red);
  background: rgba(255, 51, 102, 0.15);
  padding: 2px 8px;
  border-radius: 6px;
  margin-top: 0.4rem;
}

/* Frontier Breakthroughs Grid (Era 7) */
.frontier-breakthrough-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin: 2rem 0;
}
.frontier-card {
  background: rgba(10, 13, 24, 0.85);
  border: 1px solid var(--border-subtle);
  border-radius: 18px;
  padding: 2.2rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  transition: all var(--transition-smooth);
}
.willow-card {
  border-color: rgba(0, 240, 255, 0.35);
  box-shadow: 0 0 25px rgba(0, 240, 255, 0.1);
}
.openai-card {
  border-color: rgba(138, 43, 226, 0.35);
  box-shadow: 0 0 25px rgba(138, 43, 226, 0.1);
}
.frontier-card-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
}
.frontier-card-title {
  font-size: 1.4rem;
  line-height: 1.3;
}
.frontier-card-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.65;
}
.frontier-metrics-box {
  background: rgba(0, 0, 0, 0.4);
  border-radius: 10px;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 0.85rem;
}
.metric-line {
  display: flex;
  justify-content: space-between;
}
.metric-line span { color: var(--text-muted); }
.metric-line strong { color: var(--accent-cyan); font-family: var(--font-heading); }

/* Interactive Mini Boxes in Era 7 */
.interactive-mini-box {
  background: rgba(0, 0, 0, 0.5);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 1rem;
}
.mini-box-title {
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

/* Qubit Lattice */
.qubit-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
  margin-bottom: 0.75rem;
}
.qubit-node {
  height: 24px;
  background: rgba(0, 240, 255, 0.15);
  border: 1px solid rgba(0, 240, 255, 0.4);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--accent-cyan);
  cursor: pointer;
  transition: all 0.2s;
}
.qubit-node:hover, .qubit-node.excited {
  background: var(--accent-cyan);
  color: #000;
  box-shadow: 0 0 14px var(--accent-cyan), 0 0 28px rgba(0,240,255,0.4);
  transform: scale(1.2);
}
.qubit-node.flicker {
  background: rgba(0, 240, 255, 0.35);
  border-color: var(--accent-cyan);
}
.qubit-node.entangled {
  background: rgba(138, 43, 226, 0.45);
  border-color: var(--accent-purple);
  box-shadow: 0 0 10px var(--accent-purple);
  transform: scale(1.1);
}
.qubit-label {
  pointer-events: none;
  font-size: 0.58rem;
}
.qubit-status-row {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--accent-green);
  text-align: center;
  transition: color 0.5s;
}

/* Moore's Law Logarithmic Bar */
.moore-log-bar-track {
  width: 100%;
  height: 8px;
  background: rgba(255,255,255,0.06);
  border-radius: 4px;
  overflow: hidden;
  margin: 0.6rem 0;
}
.moore-log-bar {
  height: 100%;
  width: 2%;
  background: linear-gradient(90deg, #ffb703, #00ff88);
  border-radius: 4px;
  box-shadow: 0 0 8px rgba(0, 255, 136, 0.6);
  transition: width 0.4s ease;
}

/* Backprop Loss Bar */
.loss-bar-track {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
.loss-bar-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  white-space: nowrap;
}
.loss-bar-track-inner {
  flex: 1;
  height: 8px;
  background: rgba(255,255,255,0.06);
  border-radius: 4px;
  overflow: hidden;
}
.loss-bar {
  height: 100%;
  background: linear-gradient(90deg, #ff3366, #ffb703);
  border-radius: 4px;
  box-shadow: 0 0 6px rgba(255, 51, 102, 0.5);
  transition: width 0.4s ease;
}

/* Reasoning Scenario Tag */
.reasoning-scenario-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-purple);
  border: 1px solid rgba(138, 43, 226, 0.3);
  background: rgba(138, 43, 226, 0.08);
  border-radius: 6px;
  padding: 0.3rem 0.6rem;
  margin-bottom: 0.6rem;
  display: inline-block;
}

/* Reasoning Tree */
.reasoning-tree-display {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}
.tree-step {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  padding: 0.45rem 0.75rem;
  border-radius: 6px;
}
.step-ok {
  background: rgba(0, 255, 136, 0.12);
  color: var(--accent-green);
  border: 1px solid rgba(0, 255, 136, 0.3);
}
.step-bad {
  background: rgba(255, 51, 102, 0.12);
  color: var(--accent-red);
  border: 1px solid rgba(255, 51, 102, 0.3);
  text-decoration: line-through;
}
.small-btn {
  width: 100%;
  padding: 0.5rem 0.8rem;
  font-size: 0.82rem;
}

/* Conclusion Box */
.history-conclusion-box {
  margin-top: 3rem;
  background: linear-gradient(135deg, rgba(16, 21, 40, 0.9), rgba(11, 14, 26, 0.9));
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 3rem;
  text-align: center;
}
.history-conclusion-box h4 {
  font-size: 1.8rem;
  margin-bottom: 1rem;
}
.history-conclusion-box p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  max-width: 800px;
  margin: 0 auto 2rem auto;
}
.conclusion-cta-row {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Responsive History */
@media (max-width: 992px) {
  .history-title { font-size: 2.7rem; }
  .history-subtitle-text { font-size: 1.4rem; }
  .frontier-breakthrough-grid { grid-template-columns: 1fr; }
  .epoch-card { padding: 2rem 1.5rem; }
  .transistor-visualizer-grid { grid-template-columns: 1fr; }
  .compare-vs { display: none; }
}

@media (max-width: 768px) {
  .epoch-marker { margin-bottom: 1rem; }
  .history-title { font-size: 2.1rem; }
  .history-subtitle-text { font-size: 1.2rem; }
  .moore-display-readout { grid-template-columns: 1fr; }
}


/* ==========================================================================
   Coluna visual — arte gerada com Gemini + player de narração
   ========================================================================== */
.epoch-visual {
  grid-area: visual;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 240, 255, 0.35) transparent;
  padding-right: 0.35rem;
}

.epoch-figure {
  margin: 0;
  position: relative;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background: #05070d;
  flex: 0 0 auto;
}
.epoch-image {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  opacity: 0;
  transform: scale(1.04);
  transition: opacity 0.7s ease, transform 1.2s ease;
}
.epoch-image.is-loaded {
  opacity: 1;
  transform: scale(1);
}
.epoch-figure::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 45%, rgba(4, 5, 8, 0.85) 100%);
}
.epoch-figcaption {
  position: absolute;
  left: 0.7rem;
  bottom: 0.6rem;
  z-index: 2;
}
.ai-art-chip {
  display: inline-block;
  padding: 0.22rem 0.6rem;
  border-radius: 999px;
  background: rgba(5, 8, 17, 0.75);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* Player de narração */
.narration-player {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.75rem 0.9rem;
  border-radius: 14px;
  background: rgba(8, 10, 18, 0.8);
  border: 1px solid var(--border-light);
  flex: 0 0 auto;
}
.narration-player.is-unavailable { opacity: 0.45; }

.narration-btn {
  width: 42px;
  height: 42px;
  flex: 0 0 auto;
  border-radius: 50%;
  border: 1px solid var(--accent-cyan);
  background: rgba(0, 240, 255, 0.12);
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.narration-btn:hover:not(:disabled) {
  background: var(--accent-cyan);
  color: #050811;
  box-shadow: 0 0 18px rgba(0, 240, 255, 0.5);
}
.narration-btn:disabled { cursor: default; }
.narration-btn .icon-pause { display: none; }
.narration-player.is-playing .narration-btn .icon-play { display: none; }
.narration-player.is-playing .narration-btn .icon-pause { display: block; }

.narration-meta {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}
.narration-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.narration-track {
  height: 4px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.09);
  cursor: pointer;
  overflow: hidden;
}
.narration-fill {
  display: block;
  height: 100%;
  width: 0%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent-cyan), #00ff88);
}
.narration-time {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  flex: 0 0 auto;
}
.narration-transcript-btn {
  flex: 0 0 auto;
  padding: 0.3rem 0.6rem;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.narration-transcript-btn:hover,
.narration-transcript-btn[aria-expanded="true"] {
  color: #ffffff;
  border-color: var(--accent-cyan);
}
.narration-text {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--text-secondary);
  padding: 0.9rem 1rem;
  border-left: 2px solid var(--accent-cyan);
  background: rgba(0, 240, 255, 0.04);
  border-radius: 0 10px 10px 0;
  flex: 0 0 auto;
}

/* Corpo rolável do painel */
.epoch-body {
  grid-area: body;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 240, 255, 0.35) transparent;
  padding-right: 0.6rem;
  -webkit-mask-image: linear-gradient(180deg, transparent 0, #000 14px, #000 calc(100% - 24px), transparent 100%);
  mask-image: linear-gradient(180deg, transparent 0, #000 14px, #000 calc(100% - 24px), transparent 100%);
}
.epoch-body::-webkit-scrollbar,
.epoch-visual::-webkit-scrollbar { width: 6px; }
.epoch-body::-webkit-scrollbar-thumb,
.epoch-visual::-webkit-scrollbar-thumb {
  background: rgba(0, 240, 255, 0.3);
  border-radius: 999px;
}

/* ==========================================================================
   Responsivo — abaixo de 900px o trilho vira pilha vertical de novo
   ========================================================================== */
@media (max-width: 900px) {
  .timeline-viewport { padding: 30px 0 60px; }
  .timeline-rail {
    display: block;
    overflow: visible;
    scroll-snap-type: none;
    padding: 0 1.25rem 2rem;
  }
  .rail-nav,
  .rail-hint { display: none; }
  .epoch-section {
    flex: none;
    width: 100%;
    margin-bottom: 4.5rem;
  }
  .epoch-card {
    display: block;
    max-height: none;
    padding: 1.9rem 1.4rem;
  }
  .epoch-visual,
  .epoch-body {
    overflow: visible;
    max-height: none;
    padding-right: 0;
    -webkit-mask-image: none;
    mask-image: none;
  }
  .epoch-visual { margin-bottom: 1.8rem; }
  .timeline-scrubber {
    top: auto;
    bottom: 1rem;
    padding: 0.45rem 0.6rem;
    overflow-x: auto;
  }
  .scrubber-label,
  .scrubber-rail-progress { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .timeline-rail { scroll-behavior: auto; }
  .epoch-image { transition: none; opacity: 1; transform: none; }
}

/* No trilho horizontal a própria barra CRONOLOGIA é o eixo:
   o selo de ano só reaparece na pilha vertical (<=900px). */
@media (min-width: 901px) {
  .epoch-marker { display: none; }
}