@import url('https://fonts.googleapis.com/css2?family=Cinzel:wght@500;700&family=JetBrains+Mono:ital,wght@0,300;0,400;0,700;1,300&family=Outfit:wght@300;400;600;700&display=swap');

:root {
  --bg-dark: #030712;
  --accent-cyan: #00f0ff;
  --accent-blue: #0072ff;
  --accent-purple: #9d4edd;
  --accent-amber: #ffaa00;
  --accent-emerald: #00f5a0;
  --accent-rose: #ff0055;
  --text-main: #f0f6fc;
  --text-muted: #8b949e;
  --glass-bg: rgba(7, 15, 30, 0.65);
  --glass-border: rgba(0, 240, 255, 0.22);
  --glow-cyan: 0 0 25px rgba(0, 240, 255, 0.4);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
  -webkit-user-select: none;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: var(--bg-dark);
  font-family: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--text-main);
}

/* ============================================================================
   CINEMATIC INTRO OVERLAY
   ============================================================================ */
#intro-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1000;
  background: radial-gradient(ellipse at center, #060d1f 0%, #020408 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 1.2s cubic-bezier(0.16, 1, 0.3, 1), transform 1.2s cubic-bezier(0.16, 1, 0.3, 1);
}

#intro-overlay.hidden {
  opacity: 0;
  transform: scale(1.1);
  pointer-events: none;
}

.intro-particles {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: hidden;
}

.intro-particle {
  position: absolute;
  width: 2px;
  height: 2px;
  background: var(--accent-cyan);
  border-radius: 50%;
  animation: float-particle linear infinite;
  box-shadow: 0 0 6px var(--accent-cyan);
}

@keyframes float-particle {
  0% { transform: translateY(100vh) scale(0); opacity: 0; }
  10% { opacity: 1; }
  90% { opacity: 1; }
  100% { transform: translateY(-20px) scale(1); opacity: 0; }
}

.intro-content {
  text-align: center;
  z-index: 2;
  animation: intro-fadeIn 2s ease-out;
}

@keyframes intro-fadeIn {
  from { opacity: 0; transform: translateY(40px); }
  to { opacity: 1; transform: translateY(0); }
}

.intro-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  letter-spacing: 6px;
  color: var(--accent-cyan);
  margin-bottom: 24px;
  opacity: 0.7;
}

.intro-title {
  font-family: 'Cinzel', serif;
  font-size: 72px;
  font-weight: 700;
  letter-spacing: 8px;
  background: linear-gradient(135deg, #ffffff 0%, #a5d8ff 40%, var(--accent-cyan) 70%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: shimmer 4s ease-in-out infinite alternate;
  line-height: 1.1;
}

@keyframes shimmer {
  0% { filter: brightness(1) drop-shadow(0 0 20px rgba(0, 240, 255, 0.3)); }
  100% { filter: brightness(1.15) drop-shadow(0 0 40px rgba(0, 240, 255, 0.6)); }
}

.intro-subtitle-line {
  width: 120px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent-cyan), transparent);
  margin: 24px auto;
}

.intro-subtitle {
  font-size: 18px;
  font-weight: 300;
  color: #a5d8ff;
  letter-spacing: 3px;
  margin-bottom: 12px;
}

.intro-desc {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 32px;
}

.intro-desc em {
  font-style: italic;
  color: var(--accent-emerald);
}

.intro-scale-preview {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: var(--accent-cyan);
}

.intro-scale-line {
  width: 200px;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple), var(--accent-rose));
  border-radius: 1px;
  position: relative;
}

.intro-scale-dot {
  position: absolute;
  width: 8px;
  height: 8px;
  background: white;
  border-radius: 50%;
  top: 50%;
  transform: translateY(-50%);
  animation: scale-dot-travel 3s ease-in-out infinite;
  box-shadow: 0 0 12px var(--accent-cyan);
}

@keyframes scale-dot-travel {
  0%, 100% { left: 0%; }
  50% { left: calc(100% - 8px); }
}

.intro-start-btn {
  background: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-blue) 100%);
  color: #030b1e;
  font-weight: 700;
  border: none;
  padding: 14px 40px;
  border-radius: 12px;
  font-size: 16px;
  font-family: 'Outfit', sans-serif;
  letter-spacing: 1px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  box-shadow: 0 0 30px rgba(0, 240, 255, 0.5), 0 8px 32px rgba(0, 0, 0, 0.4);
  transition: all 0.3s ease;
  animation: btn-pulse 2s ease-in-out infinite;
}

@keyframes btn-pulse {
  0%, 100% { box-shadow: 0 0 30px rgba(0, 240, 255, 0.5), 0 8px 32px rgba(0, 0, 0, 0.4); }
  50% { box-shadow: 0 0 50px rgba(0, 240, 255, 0.8), 0 8px 32px rgba(0, 0, 0, 0.4); }
}

.intro-start-btn:hover {
  transform: scale(1.05) translateY(-2px);
  box-shadow: 0 0 60px rgba(0, 240, 255, 0.9), 0 12px 40px rgba(0, 0, 0, 0.5);
}

.intro-hint {
  margin-top: 16px;
  font-size: 11px;
  color: rgba(255,255,255,0.3);
  letter-spacing: 1px;
}

/* ============================================================================
   CANVAS & 3D VIEWPORT
   ============================================================================ */
#canvas-container {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

#webgl-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

/* Warp speed overlay canvas */
#warp-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.4s ease;
}

#warp-canvas.active {
  opacity: 1;
}

/* ============================================================================
   GLASSMORPHISM BASE
   ============================================================================ */
.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.5), inset 0 0 12px rgba(0, 240, 255, 0.05);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ============================================================================
   DEPTH INDICATOR (LEFT SIDEBAR)
   ============================================================================ */
#depth-indicator {
  position: absolute;
  left: 28px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  height: 360px;
  opacity: 0;
  transition: opacity 0.6s ease;
}

#depth-indicator.visible {
  opacity: 1;
}

.depth-track {
  position: relative;
  width: 3px;
  height: 100%;
  background: linear-gradient(to bottom, var(--accent-cyan), var(--accent-blue), var(--accent-emerald), var(--accent-purple), var(--accent-rose));
  border-radius: 2px;
  box-shadow: 0 0 12px rgba(0, 240, 255, 0.3);
}

.depth-marker {
  position: absolute;
  top: 5%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: white;
  border: 3px solid var(--accent-cyan);
  box-shadow: 0 0 20px var(--accent-cyan), 0 0 40px rgba(0, 240, 255, 0.4);
  transition: top 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 2;
}

.depth-notch {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 12px;
  height: 2px;
  background: rgba(255,255,255,0.3);
  border-radius: 1px;
}

.depth-notch::after {
  content: attr(data-label);
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-family: 'JetBrains Mono', monospace;
  font-size: 9px;
  color: var(--text-muted);
  white-space: nowrap;
  letter-spacing: 1px;
}

.depth-labels {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  height: 100%;
  position: absolute;
  left: -6px;
}

.depth-top-label, .depth-bot-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 8px;
  color: var(--accent-cyan);
  transform: rotate(-90deg);
  white-space: nowrap;
}

/* ============================================================================
   HEADER HUD
   ============================================================================ */
#hud-header {
  position: absolute;
  top: 24px;
  left: 68px;
  z-index: 10;
  display: flex;
  flex-direction: column;
  gap: 4px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.6s ease;
}

#hud-header.visible {
  opacity: 1;
}

.logo-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-badge::before {
  content: '';
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 10px var(--accent-cyan);
  animation: pulse-glow 2s infinite ease-in-out;
}

@keyframes pulse-glow {
  0%, 100% { opacity: 0.4; transform: scale(0.9); }
  50% { opacity: 1; transform: scale(1.2); }
}

.main-title {
  font-family: 'Cinzel', serif;
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 2px;
  background: linear-gradient(135deg, #ffffff 0%, #a5d8ff 50%, var(--accent-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 12px;
  font-weight: 300;
  color: var(--text-muted);
  letter-spacing: 1px;
}

/* ============================================================================
   TOP RIGHT CONTROLS
   ============================================================================ */
#hud-top-right {
  position: absolute;
  top: 24px;
  right: 28px;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 12px;
  opacity: 0;
  transition: opacity 0.6s ease;
}

#hud-top-right.visible {
  opacity: 1;
}

.hud-btn {
  background: rgba(10, 25, 47, 0.7);
  border: 1px solid rgba(0, 240, 255, 0.25);
  color: #e2e8f0;
  padding: 8px 16px;
  border-radius: 8px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.25s ease;
  backdrop-filter: blur(10px);
}

.hud-btn:hover {
  background: rgba(0, 240, 255, 0.15);
  border-color: var(--accent-cyan);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.3);
  transform: translateY(-1px);
  color: #ffffff;
}

.hud-btn.active {
  background: rgba(0, 240, 255, 0.2);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.35);
}

.hud-btn svg {
  width: 15px;
  height: 15px;
  fill: currentColor;
}

/* ============================================================================
   METRIC SCALE INDICATOR (TOP CENTER)
   ============================================================================ */
#scale-telemetry {
  position: absolute;
  top: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  padding: 10px 24px;
  text-align: center;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.6s ease;
}

#scale-telemetry.visible {
  opacity: 1;
}

.scale-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--accent-cyan);
}

.scale-value {
  font-family: 'JetBrains Mono', monospace;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 1px;
  color: #ffffff;
  text-shadow: 0 0 12px rgba(0, 240, 255, 0.6);
  transition: color 0.5s ease;
}

.scale-comparison {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 2px;
}

/* ============================================================================
   BOTTOM HUD: PLAYBACK & SCALE NAVIGATOR
   ============================================================================ */
#bottom-hud {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  width: calc(100% - 56px);
  max-width: 1050px;
  padding: 16px 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  opacity: 0;
  transition: opacity 0.6s ease;
}

#bottom-hud.visible {
  opacity: 1;
}

/* ============================================================================
   SCALE STAGE PILLS
   ============================================================================ */
.stage-pills {
  display: flex;
  justify-content: space-between;
  position: relative;
  gap: 8px;
}

.stage-pill {
  flex: 1;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 8px 10px;
  border-radius: 8px;
  text-align: center;
  cursor: pointer;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.stage-pill::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 50% 120%, var(--accent-cyan), transparent 70%);
  opacity: 0;
  transition: opacity 0.35s ease;
}

.stage-pill:hover {
  background: rgba(0, 240, 255, 0.1);
  border-color: rgba(0, 240, 255, 0.4);
  transform: translateY(-2px);
}

.stage-pill:hover::before {
  opacity: 0.15;
}

.stage-pill.active {
  background: rgba(0, 240, 255, 0.18);
  border-color: var(--accent-cyan);
  box-shadow: 0 0 18px rgba(0, 240, 255, 0.35), inset 0 -2px 8px rgba(0, 240, 255, 0.1);
}

.stage-pill.active::before {
  opacity: 0.2;
}

.stage-pill .pill-icon {
  font-size: 14px;
  display: block;
  margin-bottom: 2px;
  position: relative;
  z-index: 1;
}

.stage-pill .pill-num {
  font-family: 'JetBrains Mono', monospace;
  font-size: 9px;
  font-weight: 700;
  color: var(--accent-cyan);
  display: block;
  position: relative;
  z-index: 1;
}

.stage-pill .pill-title {
  font-size: 11px;
  font-weight: 600;
  color: #fff;
  white-space: nowrap;
  position: relative;
  z-index: 1;
}

.stage-pill .pill-order {
  font-family: 'JetBrains Mono', monospace;
  font-size: 9px;
  color: var(--text-muted);
  position: relative;
  z-index: 1;
}

/* ============================================================================
   ZOOM SCRUBBER SLIDER
   ============================================================================ */
.slider-container {
  display: flex;
  align-items: center;
  gap: 16px;
}

.slider-endpoint {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  color: var(--accent-cyan);
  font-weight: 700;
  min-width: 65px;
}

.slider-endpoint.right {
  text-align: right;
  color: var(--accent-purple);
}

.custom-range {
  flex: 1;
  -webkit-appearance: none;
  height: 6px;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--accent-cyan) 0%, var(--accent-blue) 35%, var(--accent-emerald) 60%, var(--accent-purple) 85%, var(--accent-rose) 100%);
  outline: none;
  cursor: pointer;
  position: relative;
  box-shadow: 0 0 10px rgba(0, 240, 255, 0.2);
}

.custom-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: #ffffff;
  border: 3px solid var(--accent-cyan);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.9);
  cursor: grab;
  transition: transform 0.15s ease;
}

.custom-range::-webkit-slider-thumb:hover {
  transform: scale(1.25);
}

.custom-range::-webkit-slider-thumb:active {
  cursor: grabbing;
  transform: scale(1.35);
  box-shadow: 0 0 25px rgba(0, 240, 255, 1);
}

/* ============================================================================
   PLAYBACK TOOLBAR
   ============================================================================ */
.playback-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.playback-controls {
  display: flex;
  align-items: center;
  gap: 10px;
}

.play-tour-btn {
  background: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-blue) 100%);
  color: #030b1e;
  font-weight: 700;
  border: none;
  padding: 8px 20px;
  border-radius: 8px;
  font-size: 12px;
  font-family: 'Outfit', sans-serif;
  letter-spacing: 0.5px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.4);
  transition: all 0.25s ease;
}

.play-tour-btn:hover {
  box-shadow: 0 0 30px rgba(0, 240, 255, 0.7);
  transform: scale(1.03);
}

.play-tour-btn svg {
  width: 14px;
  height: 14px;
  fill: currentColor;
}

.speed-select {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #cbd5e1;
  padding: 6px 12px;
  border-radius: 6px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  cursor: pointer;
  outline: none;
}

.speed-select option {
  background: #0b1329;
  color: #fff;
}

.playback-hints {
  font-size: 11px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 16px;
}

.hint-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.key-kbd {
  background: rgba(255, 255, 255, 0.1);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  color: var(--accent-cyan);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

/* ============================================================================
   SCIENTIFIC INFO CARD (FLOATING RIGHT)
   ============================================================================ */
#info-card {
  position: absolute;
  top: 90px;
  right: 28px;
  width: 340px;
  padding: 20px 24px;
  z-index: 10;
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-height: calc(100vh - 270px);
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--accent-cyan) transparent;
  opacity: 0;
  transition: opacity 0.6s ease, transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  transform: translateX(10px);
}

#info-card.visible {
  opacity: 1;
  transform: translateX(0);
}

#info-card::-webkit-scrollbar {
  width: 4px;
}

#info-card::-webkit-scrollbar-thumb {
  background: var(--accent-cyan);
  border-radius: 2px;
}

.card-category {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--accent-cyan);
}

.card-title {
  font-family: 'Outfit', sans-serif;
  font-size: 19px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.25;
}

.card-metric {
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: var(--accent-amber);
  background: rgba(255, 170, 0, 0.08);
  padding: 4px 10px;
  border-radius: 6px;
  border-left: 2px solid var(--accent-amber);
  display: inline-block;
}

.card-body {
  font-size: 12.5px;
  line-height: 1.6;
  color: #cbd5e1;
  font-weight: 300;
}

.card-specs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 4px;
  padding-top: 8px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.spec-item {
  display: flex;
  flex-direction: column;
}

.spec-name {
  font-family: 'JetBrains Mono', monospace;
  font-size: 9px;
  text-transform: uppercase;
  color: var(--text-muted);
}

.spec-val {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 600;
  color: var(--accent-emerald);
}

.card-equation {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(0, 240, 255, 0.15);
  border-radius: 6px;
  padding: 8px 12px;
  text-align: center;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: #7dd3fc;
  margin-top: 4px;
  letter-spacing: 0.5px;
}

/* ============================================================================
   NOTIFICATION TOAST
   ============================================================================ */
#toast {
  position: absolute;
  top: 85px;
  left: 50%;
  transform: translateX(-50%) translateY(-20px);
  background: rgba(3, 10, 24, 0.9);
  border: 1px solid var(--accent-cyan);
  padding: 8px 20px;
  border-radius: 20px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  color: var(--accent-cyan);
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s ease;
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.3);
}

#toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ============================================================================
   SCALE TRANSITION FLASH
   ============================================================================ */
.scale-flash {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 50;
  pointer-events: none;
  background: radial-gradient(circle, rgba(0, 240, 255, 0.15), transparent 70%);
  opacity: 0;
  animation: flash-burst 0.8s ease-out forwards;
}

@keyframes flash-burst {
  0% { opacity: 1; transform: scale(0.8); }
  100% { opacity: 0; transform: scale(1.5); }
}

/* ============================================================================
   ANNOTATION LABELS SYSTEM (Leader Lines + Floating Labels)
   ============================================================================ */
#annotation-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 3;
  pointer-events: none;
}

#annotations-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 4;
  pointer-events: none;
}

.annotation-label {
  position: absolute;
  display: flex;
  align-items: center;
  gap: 8px;
  opacity: 0;
  transition: opacity 0.6s ease, transform 0.4s ease;
  transform: translateY(4px);
  pointer-events: none;
}

.annotation-label.visible {
  opacity: 1;
  transform: translateY(0);
}

.annotation-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 8px var(--accent-cyan), 0 0 16px rgba(0, 240, 255, 0.4);
  border: 1.5px solid rgba(255, 255, 255, 0.8);
  flex-shrink: 0;
  animation: annotation-pulse 2.5s ease-in-out infinite;
}

@keyframes annotation-pulse {
  0%, 100% { box-shadow: 0 0 8px var(--accent-cyan), 0 0 16px rgba(0, 240, 255, 0.4); }
  50% { box-shadow: 0 0 12px var(--accent-cyan), 0 0 24px rgba(0, 240, 255, 0.6); }
}

.annotation-text {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 2px;
  color: rgba(255, 255, 255, 0.85);
  text-transform: uppercase;
  white-space: nowrap;
  text-shadow: 0 0 8px rgba(0, 0, 0, 0.8), 0 1px 4px rgba(0, 0, 0, 0.6);
  padding: 3px 8px;
  background: rgba(0, 10, 30, 0.45);
  border-radius: 4px;
  border: 1px solid rgba(0, 240, 255, 0.15);
  backdrop-filter: blur(4px);
}

/* ============================================================================
   BOTTOM-LEFT SCIENTIFIC DESCRIPTION PANEL
   ============================================================================ */
#sci-description {
  position: absolute;
  bottom: 180px;
  left: 68px;
  z-index: 10;
  max-width: 360px;
  opacity: 0;
  transition: opacity 0.6s ease, transform 0.5s ease;
  transform: translateY(10px);
  pointer-events: none;
}

#sci-description.visible {
  opacity: 1;
  transform: translateY(0);
}

.sci-scale-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  letter-spacing: 2.5px;
  color: var(--accent-cyan);
  margin-bottom: 6px;
  text-transform: uppercase;
  opacity: 0.8;
}

.sci-title {
  font-family: 'Outfit', sans-serif;
  font-size: 28px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.2;
  margin-bottom: 10px;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.5);
}

.sci-body {
  font-family: 'Outfit', sans-serif;
  font-size: 13px;
  font-weight: 300;
  line-height: 1.65;
  color: rgba(203, 213, 225, 0.85);
  max-width: 340px;
}

/* ============================================================================
   RESPONSIVE
   ============================================================================ */
@media (max-width: 900px) {
  #info-card {
    display: none;
  }
  .stage-pill .pill-order {
    display: none;
  }
  .stage-pill .pill-icon {
    display: none;
  }
  .main-title {
    font-size: 20px;
  }
  .intro-title {
    font-size: 40px;
    letter-spacing: 4px;
  }
  #depth-indicator {
    display: none;
  }
  #hud-header {
    left: 28px;
  }
  .playback-hints {
    display: none;
  }
  #annotations-layer, #annotation-canvas {
    display: none;
  }
  #sci-description {
    left: 28px;
    bottom: 200px;
    max-width: 260px;
  }
  .sci-title {
    font-size: 20px;
  }
}