/* ==========================================================================
   Quantum Entanglement — Стили
   Легко интегрируется в Laravel Blade
   ========================================================================== */

/* --- Variables --------------------------------------------------------- */
:root {
  --bg-deep: #0a0a1a;
  --bg-section: #0d0d24;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-card-hover: rgba(255, 255, 255, 0.06);
  --text-primary: #e8e8f0;
  --text-secondary: #9999b3;
  --cyan: #00f0ff;
  --magenta: #ff00aa;
  --gold: #ffd700;
  --green: #00ff88;
  --purple: #8b5cf6;
  --orange: #ff6633;
  --red: #ff3366;
  --glow-cyan: 0 0 30px rgba(0, 240, 255, 0.15);
  --glow-magenta: 0 0 30px rgba(255, 0, 170, 0.15);
  --glow-gold: 0 0 30px rgba(255, 215, 0, 0.12);
  --glow-green: 0 0 30px rgba(0, 255, 136, 0.12);
  --font-sans: 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
  --transition: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* --- Reset & Base ----------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: var(--cyan) transparent;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-deep);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* --- Scrollbar -------------------------------------------------------- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--cyan); border-radius: 3px; }

/* --- Canvas (particles) ----------------------------------------------- */
#particles-canvas {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  z-index: 0;
  pointer-events: none;
}

/* --- Navigation ------------------------------------------------------- */
.quantum-nav {
  position: fixed;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.quantum-nav a {
  display: block;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  border: 2px solid transparent;
  transition: var(--transition);
  position: relative;
  cursor: pointer;
}

.quantum-nav a:hover,
.quantum-nav a.active {
  background: var(--cyan);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.4);
  border-color: var(--cyan);
  transform: scale(1.3);
}

.quantum-nav a .nav-tooltip {
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(0, 0, 0, 0.85);
  color: var(--text-primary);
  font-size: 0.7rem;
  padding: 4px 12px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: var(--transition);
  border: 1px solid rgba(0, 240, 255, 0.2);
  font-family: var(--font-mono);
}

.quantum-nav a:hover .nav-tooltip,
.quantum-nav a:focus .nav-tooltip,
.quantum-nav a:focus-visible .nav-tooltip {
  opacity: 1;
  right: 30px;
}

.quantum-nav a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 4px;
}

/* --- Sections --------------------------------------------------------- */
.section {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  padding: 80px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Subtle section glow border at top */
.section::before {
  content: '';
  position: absolute;
  top: 0; left: 50%;
  transform: translateX(-50%);
  width: 40%; height: 1px;
  background: linear-gradient(90deg, transparent, var(--section-accent), transparent);
  opacity: 0.08;
  pointer-events: none;
}

.section-inner {
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
  position: relative;
}

.section-hero::before { display: none; }

/* Section accent colours */
.section-hero { --section-accent: var(--cyan); }
.section-doubleslit { --section-accent: var(--cyan); }
.section-mystery { --section-accent: var(--gold); }
.section-what-is { --section-accent: var(--gold); }
.section-epr { --section-accent: var(--magenta); }
.section-bell { --section-accent: var(--green); }
.section-experiments { --section-accent: var(--purple); }
.section-loopholes { --section-accent: var(--orange); }
.section-interpretations { --section-accent: var(--red); }
.section-conclusion { --section-accent: var(--cyan); }

/* --- Hero Section ----------------------------------------------------- */
.section-hero {
  min-height: 100vh;
  text-align: center;
  flex-direction: column;
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-subtitle {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--cyan);
  text-transform: uppercase;
  letter-spacing: 6px;
  margin-bottom: 24px;
  opacity: 0;
  animation: fadeUp 1s 0.3s forwards;
}

.hero-title {
  font-size: clamp(2.8rem, 8vw, 6rem);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 16px;
  opacity: 0;
  animation: fadeUp 1s 0.6s forwards;
  background: linear-gradient(135deg, var(--cyan), var(--magenta), var(--gold));
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 0 60px rgba(0, 240, 255, 0.15));
}

.hero-description {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto 40px;
  opacity: 0;
  animation: fadeUp 1s 0.9s forwards;
  line-height: 1.8;
}

.hero-scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 0.75rem;
  font-family: var(--font-mono);
  letter-spacing: 2px;
  opacity: 0;
  animation: fadeUp 1s 1.2s forwards;
}

.hero-scroll-indicator .scroll-arrow {
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--cyan);
  border-bottom: 2px solid var(--cyan);
  transform: rotate(45deg);
  animation: bounce 2s infinite;
}

/* --- Typography ------------------------------------------------------- */
h2 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  margin-bottom: 12px;
  position: relative;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--section-accent);
  text-transform: uppercase;
  letter-spacing: 4px;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}

/* Decorative line before section label */
.section-label::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--section-accent);
  opacity: 0.3;
}

.section-title {
  background: linear-gradient(135deg, var(--section-accent), #fff);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 24px;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 700px;
  margin-bottom: 48px;
  line-height: 1.8;
  position: relative;
  padding-bottom: 16px;
}

/* Decorative gradient underline for subtitles */
.section-subtitle::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 60px; height: 2px;
  background: linear-gradient(90deg, var(--section-accent), transparent);
  opacity: 0.3;
  border-radius: 1px;
}

/* Regular paragraphs with subtle left accent */
.section-inner > p {
  position: relative;
  padding-left: 0;
  transition: padding-left 0.4s ease;
}

.section-inner > p:not(.hero-description):not(.chsh-hint):not(.entangled-state-label) {
  padding-left: 16px;
}

.section-inner > p:not(.hero-description):not(.chsh-hint):not(.entangled-state-label)::before {
  content: '';
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 2px;
  background: linear-gradient(to bottom, var(--section-accent), transparent);
  opacity: 0.12;
  border-radius: 1px;
  transition: opacity 0.4s ease;
}

.section-inner > p:not(.hero-description):not(.chsh-hint):not(.entangled-state-label):hover::before {
  opacity: 0.3;
}

p {
  margin-bottom: 1.2rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* --- Cards & Grids ---------------------------------------------------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  margin: 32px 0;
}

.card {
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 16px;
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 3px;
  background: var(--section-accent);
  opacity: 0;
  transition: var(--transition);
}

.card:hover {
  background: var(--bg-card-hover);
  transform: translateY(-4px);
  border-color: rgba(255, 255, 255, 0.12);
}

.card:hover::before {
  opacity: 1;
}

.card h3 {
  font-size: 1.15rem;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.card p {
  font-size: 0.92rem;
  margin-bottom: 0;
}

.card-icon {
  font-size: 2rem;
  margin-bottom: 16px;
  display: block;
}

/* --- Mini Visualizations (replace emoji icons) ----------------------- */
.mini-vis {
  width: 100%;
  height: 48px;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  position: relative;
}

/* Chain / link visual */
.mini-chain {
  display: flex;
  align-items: center;
  gap: 2px;
}
.mini-chain-link {
  width: 16px; height: 8px;
  border: 2px solid var(--section-accent);
  border-radius: 2px;
  position: relative;
}
.mini-chain-link::after {
  content: '';
  position: absolute;
  top: -3px; left: 4px;
  width: 4px; height: 14px;
  background: transparent;
  border: 2px solid var(--section-accent);
  border-radius: 2px;
}
.mini-chain-link + .mini-chain-link { margin-left: 1px; }

/* Correlation wave visual */
.mini-correlation {
  display: flex;
  align-items: flex-end;
  height: 100%;
  gap: 3px;
}
.mini-correlation .bar {
  width: 4px;
  border-radius: 2px 2px 0 0;
  background: linear-gradient(to top, var(--section-accent), transparent);
  animation: miniPulse 2s ease-in-out infinite;
}
.mini-correlation .bar:nth-child(1) { height: 60%; animation-delay: 0s; }
.mini-correlation .bar:nth-child(2) { height: 90%; animation-delay: 0.1s; }
.mini-correlation .bar:nth-child(3) { height: 75%; animation-delay: 0.2s; }
.mini-correlation .bar:nth-child(4) { height: 95%; animation-delay: 0.3s; }
.mini-correlation .bar:nth-child(5) { height: 40%; animation-delay: 0.4s; }

/* Hidden variable / question visual */
.mini-hidden {
  position: relative;
  width: 36px; height: 36px;
}
.mini-hidden-circle {
  width: 100%; height: 100%;
  border: 2px dashed var(--section-accent);
  border-radius: 50%;
  animation: miniSpin 4s linear infinite;
}
.mini-hidden-q {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  font-size: 1rem;
  color: var(--section-accent);
  font-weight: 700;
  font-family: var(--font-mono);
}

/* Wave interference mini */
.mini-interference {
  display: flex;
  align-items: flex-end;
  height: 100%;
  gap: 2px;
  width: 100%;
  justify-content: center;
}
.mini-interference .bar {
  width: 4px;
  border-radius: 2px 2px 0 0;
  background: linear-gradient(to top, var(--section-accent), transparent);
  animation: miniWave 1.5s ease-in-out infinite;
}
.mini-interference .bar:nth-child(1) { height: 20%; animation-delay: 0s; }
.mini-interference .bar:nth-child(2) { height: 60%; animation-delay: 0.1s; }
.mini-interference .bar:nth-child(3) { height: 85%; animation-delay: 0.15s; }
.mini-interference .bar:nth-child(4) { height: 50%; animation-delay: 0.2s; }
.mini-interference .bar:nth-child(5) { height: 15%; animation-delay: 0.25s; }
.mini-interference .bar:nth-child(6) { height: 70%; animation-delay: 0.3s; }
.mini-interference .bar:nth-child(7) { height: 90%; animation-delay: 0.35s; }
.mini-interference .bar:nth-child(8) { height: 40%; animation-delay: 0.4s; }
.mini-interference .bar:nth-child(9) { height: 10%; animation-delay: 0.45s; }

/* Particle dots mini */
.mini-particles {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
}
.mini-particle-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--section-accent);
  animation: miniFloat 3s ease-in-out infinite;
}
.mini-particle-dot:nth-child(2) { animation-delay: 0.3s; width: 10px; height: 10px; }
.mini-particle-dot:nth-child(3) { animation-delay: 0.6s; }
.mini-particle-dot:nth-child(4) { animation-delay: 0.9s; width: 6px; height: 6px; }
.mini-particle-dot:nth-child(5) { animation-delay: 1.2s; }

/* Observer eye mini */
.mini-eye {
  position: relative;
  width: 40px; height: 24px;
  border: 2px solid var(--section-accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}
.mini-eye-pupil {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--section-accent);
  animation: miniLook 3s ease-in-out infinite;
}

/* Collapse mini */
.mini-collapse {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}
.mini-collapse .dot {
  width: 12px; height: 12px;
  border-radius: 50%;
  transition: all 0.5s ease;
}
.mini-collapse .dot:first-child {
  background: var(--cyan);
  box-shadow: 0 0 8px rgba(0,240,255,0.4);
  animation: miniCollapseLeft 3s ease-in-out infinite;
}
.mini-collapse .dot:last-child {
  background: var(--magenta);
  box-shadow: 0 0 8px rgba(255,0,170,0.4);
  animation: miniCollapseRight 3s ease-in-out infinite;
}
.mini-collapse-line {
  width: 16px; height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--magenta));
  position: relative;
}
.mini-collapse-line::after {
  content: '∞';
  position: absolute;
  top: -7px; left: 50%;
  transform: translateX(-50%);
  font-size: 0.7rem;
  color: rgba(255,255,255,0.2);
}

@keyframes miniPulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}
@keyframes miniSpin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}
@keyframes miniWave {
  0%, 100% { transform: scaleY(1); }
  50% { transform: scaleY(0.7); }
}
@keyframes miniFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}
@keyframes miniLook {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}
@keyframes miniCollapseLeft {
  0%, 100% { transform: scale(1); opacity: 0.7; }
  50% { transform: scale(0.8); opacity: 1; }
}
@keyframes miniCollapseRight {
  0%, 100% { transform: scale(1); opacity: 0.7; }
  50% { transform: scale(0.8); opacity: 1; }
}

/* Distance / locality mini (two dots with dashed line) */
.mini-distance {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
  width: 100%;
}
.mini-distance-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  background: var(--section-accent);
  position: relative;
}
.mini-distance-dot::after {
  content: '';
  position: absolute;
  width: 2px; height: 2px;
  background: var(--section-accent);
  border-radius: 50%;
}
.mini-distance-line {
  width: 24px; height: 2px;
  border-top: 1px dashed var(--section-accent);
  position: relative;
  animation: miniDistancePulse 2s ease-in-out infinite;
}
.mini-distance-line::after {
  content: '→';
  position: absolute;
  right: -6px; top: -7px;
  font-size: 0.5rem;
  color: var(--section-accent);
}

/* Target / freedom of choice (concentric circles) */
.mini-target {
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 2px solid var(--section-accent);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}
.mini-target::before {
  content: '';
  width: 22px; height: 22px;
  border-radius: 50%;
  border: 2px solid var(--section-accent);
  opacity: 0.6;
}
.mini-target::after {
  content: '';
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--section-accent);
  position: absolute;
  animation: miniPulse 2s ease-in-out infinite;
}

/* Nonlocal / hidden connection (zigzag line between dots) */
.mini-nonlocal {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 3px;
  width: 100%;
}
.mini-nonlocal-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  background: var(--section-accent);
  animation: miniPulse 2s ease-in-out infinite;
}
.mini-nonlocal-dot:first-child { background: var(--cyan); }
.mini-nonlocal-dot:last-child { background: var(--magenta); }
.mini-nonlocal-line {
  width: 20px; height: 12px;
  position: relative;
}
.mini-nonlocal-line::before {
  content: '';
  position: absolute;
  width: 100%; height: 100%;
  background: 
    linear-gradient(45deg, transparent 33%, var(--section-accent) 33%, var(--section-accent) 37%, transparent 37%),
    linear-gradient(-45deg, transparent 33%, var(--section-accent) 33%, var(--section-accent) 37%, transparent 37%);
  opacity: 0.5;
  animation: miniZap 2s ease-in-out infinite;
}

/* Loop / circular arrows (superdeterminism) */
.mini-loop {
  width: 32px; height: 32px;
  border-radius: 50%;
  border: 2px solid transparent;
  border-top-color: var(--section-accent);
  border-right-color: var(--section-accent);
  animation: miniSpin 2s linear infinite;
  position: relative;
}
.mini-loop::after {
  content: '';
  position: absolute;
  top: -4px; right: -4px;
  width: 6px; height: 6px;
  border-top: 2px solid var(--section-accent);
  border-right: 2px solid var(--section-accent);
  transform: rotate(45deg);
}

/* Checkmark / verified (conclusion) */
.mini-check {
  width: 32px; height: 32px;
  border-radius: 50%;
  border: 2px solid var(--green);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 16px rgba(0,255,136,0.2);
  animation: miniPulse 2s ease-in-out infinite;
}
.mini-check::after {
  content: '';
  width: 12px; height: 6px;
  border-left: 2px solid var(--green);
  border-bottom: 2px solid var(--green);
  transform: rotate(-45deg) translateY(-2px);
  position: absolute;
  top: 11px;
}

/* Future / star (conclusion) */
.mini-future {
  width: 36px; height: 36px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}
.mini-future-diamond {
  width: 20px; height: 20px;
  background: var(--section-accent);
  transform: rotate(45deg) scale(0.7);
  opacity: 0.5;
  box-shadow: 0 0 20px var(--section-accent);
  animation: miniPulse 2s ease-in-out infinite;
}
.mini-future::before, .mini-future::after {
  content: '✦';
  position: absolute;
  font-size: 0.4rem;
  color: var(--section-accent);
  animation: miniFloat 3s ease-in-out infinite;
}
.mini-future::before { top: 0; left: 2px; animation-delay: 0.5s; }
.mini-future::after { bottom: 0; right: 2px; animation-delay: 1s; }

/* Scale / balance (Bell proof) */
.mini-scale {
  width: 40px; height: 36px;
  position: relative;
  display: flex;
  align-items: flex-start;
  justify-content: center;
}
.mini-scale-beam {
  width: 30px; height: 2px;
  background: var(--section-accent);
  position: relative;
  top: 4px;
}
.mini-scale-beam::before, .mini-scale-beam::after {
  content: '';
  position: absolute;
  top: 2px;
  width: 2px; height: 14px;
  background: var(--section-accent);
}
.mini-scale-beam::before { left: 3px; }
.mini-scale-beam::after { right: 3px; }
.mini-scale-beam .pivot {
  position: absolute;
  top: -6px; left: 50%;
  transform: translateX(-50%);
  width: 0; height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-bottom: 8px solid var(--section-accent);
}
.mini-scale-pan {
  position: absolute;
  bottom: 0;
  width: 10px; height: 3px;
  background: var(--section-accent);
  opacity: 0.5;
}
.mini-scale-pan:first-child { left: 0; }
.mini-scale-pan:last-child { right: 0; }

/* Paradox mini (two overlapping circles) */
.mini-paradox {
  width: 36px; height: 36px;
  position: relative;
}
.mini-paradox-circle {
  position: absolute;
  width: 22px; height: 22px;
  border-radius: 50%;
  border: 2px solid var(--section-accent);
  opacity: 0.5;
}
.mini-paradox-circle:first-child {
  left: 0; top: 2px;
  border-color: var(--cyan);
  animation: miniFloat 3s ease-in-out infinite;
}
.mini-paradox-circle:last-child {
  right: 0; bottom: 2px;
  border-color: var(--magenta);
  animation: miniFloat 3s ease-in-out infinite reverse;
}
.mini-paradox-q {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: var(--section-accent);
  font-weight: 700;
}

/* --- Box with gloves (перчатки analogy) ----------------------------- */
.mini-box {
  width: 44px; height: 36px;
  position: relative;
}
.mini-box-body {
  position: absolute;
  inset: 0;
  border: 2px solid var(--section-accent);
  border-radius: 4px;
  background: rgba(255,255,255,0.02);
}
.mini-box-body::before {
  content: '';
  position: absolute;
  top: -3px; left: -2px; right: -2px;
  height: 4px;
  background: var(--section-accent);
  opacity: 0.25;
  border-radius: 3px 3px 0 0;
}
.mini-box-glove {
  position: absolute;
  width: 12px; height: 18px;
  border-radius: 6px 6px 3px 3px;
  bottom: 6px;
}
.mini-box-glove.left {
  left: 7px;
  background: linear-gradient(135deg, var(--cyan), #008899);
  opacity: 0.5;
  animation: miniGlovePull 3s ease-in-out infinite;
}
.mini-box-glove.right {
  right: 7px;
  background: linear-gradient(135deg, var(--magenta), #880066);
  opacity: 0.8;
  animation: miniGloveStay 3s ease-in-out infinite;
}
.mini-box-lid {
  position: absolute;
  top: -5px;
  width: 100%;
  text-align: center;
  font-size: 0.5rem;
  color: var(--section-accent);
  opacity: 0.5;
  animation: miniLidOpen 3s ease-in-out infinite;
}

@keyframes miniLidOpen {
  0%, 100% { transform: translateY(0); opacity: 0.5; }
  50% { transform: translateY(-4px); opacity: 0.2; }
}

/* --- Hidden values electron (скрытые параметры) --------------------- */
.mini-hidden-values {
  width: 42px; height: 42px;
  position: relative;
}
.mini-hidden-electron {
  width: 22px; height: 22px;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, var(--section-accent), transparent);
  border: 1.5px solid var(--section-accent);
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  animation: miniElectronPulse 3s ease-in-out infinite;
  z-index: 1;
}
.mini-hidden-tag {
  position: absolute;
  font-size: 0.35rem;
  font-family: var(--font-mono);
  color: var(--text-secondary);
  padding: 1px 4px;
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 2px;
  background: rgba(0,0,0,0.3);
  white-space: nowrap;
  z-index: 2;
}
.mini-hidden-tag.t1 { top: 0; left: 50%; transform: translateX(-50%); }
.mini-hidden-tag.t2 { bottom: 2px; left: -2px; }
.mini-hidden-tag.t3 { bottom: 2px; right: -2px; }
.mini-hidden-tag.highlight {
  background: var(--section-accent);
  color: #000;
  border-color: var(--section-accent);
  animation: none;
}

@keyframes miniElectronPulse {
  0%, 100% { box-shadow: 0 0 6px var(--section-accent); }
  50% { box-shadow: 0 0 16px var(--section-accent); opacity: 0.7; }
}

/* --- Einstein vs Bohr profiles -------------------------------------- */
.mini-einstein-bohr {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
}
.mini-eb-fig {
  width: 20px; height: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.55rem;
  font-weight: 700;
  color: #fff;
  position: relative;
  animation: miniEBob 3s ease-in-out infinite;
}
.mini-eb-fig.ein {
  background: radial-gradient(circle at 40% 40%, var(--cyan), #004466);
  box-shadow: 0 0 12px rgba(0,240,255,0.3);
}
.mini-eb-fig.bohr {
  background: radial-gradient(circle at 40% 40%, var(--gold), #554400);
  box-shadow: 0 0 12px rgba(255,215,0,0.3);
  animation-delay: 1.5s;
}
.mini-eb-fig.ein::after {
  content: '⚡';
  position: absolute;
  right: -8px; top: -4px;
  font-size: 0.4rem;
  animation: miniSpark 1.5s ease-in-out infinite;
}
.mini-eb-fig.bohr::after {
  content: '⚡';
  position: absolute;
  left: -8px; top: -4px;
  font-size: 0.4rem;
  animation: miniSpark 1.5s ease-in-out infinite 0.75s;
}
.mini-eb-line {
  width: 8px; height: 1px;
  background: var(--section-accent);
  opacity: 0.3;
  animation: miniEBLine 3s ease-in-out infinite;
}

@keyframes miniEBob {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-3px); }
}
@keyframes miniSpark {
  0%, 100% { opacity: 0; transform: scale(0.5); }
  50% { opacity: 0.8; transform: scale(1); }
}
@keyframes miniEBLine {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 0.7; }
}
@keyframes miniGlovePull {
  0%, 100% { transform: translate(0, 0); opacity: 0.5; }
  50% { transform: translate(-4px, -4px); opacity: 0.2; }
}
@keyframes miniGloveStay {
  0%, 100% { opacity: 0.8; }
  50% { opacity: 0.5; }
}

/* --- Uncertainty principle (position vs momentum) ------------------- */
.mini-uncertainty {
  width: 40px; height: 40px;
  position: relative;
}
.mini-uncertainty-cross {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 100%; height: 100%;
}
.mini-uncertainty-cross::before,
.mini-uncertainty-cross::after {
  content: '';
  position: absolute;
  background: var(--section-accent);
  opacity: 0.12;
}
.mini-uncertainty-cross::before {
  width: 100%; height: 1px;
  top: 50%;
}
.mini-uncertainty-cross::after {
  width: 1px; height: 100%;
  left: 50%;
}
.mini-uncertainty-label {
  position: absolute;
  font-size: 0.4rem;
  font-family: var(--font-mono);
  color: var(--text-secondary);
}
.mini-uncertainty-label.lx { bottom: -2px; right: 4px; }
.mini-uncertainty-label.lp { top: -2px; left: 4px; }
.mini-uncertainty-bar {
  position: absolute;
  border-radius: 2px;
  background: var(--section-accent);
}
.mini-uncertainty-bar.dx {
  height: 3px;
  top: 50%; left: 4px; right: 4px;
  transform: translateY(-50%);
  animation: miniUncertainDX 3s ease-in-out infinite;
}
.mini-uncertainty-bar.dp {
  width: 3px;
  left: 50%; top: 4px; bottom: 4px;
  transform: translateX(-50%);
  animation: miniUncertainDP 3s ease-in-out infinite;
}

@keyframes miniUncertainDX {
  0%, 100% { right: 20%; opacity: 0.5; }
  50% { right: 4px; opacity: 0.9; }
}
@keyframes miniUncertainDP {
  0%, 100% { bottom: 20%; opacity: 0.5; }
  50% { bottom: 4px; opacity: 0.9; }
}

@keyframes miniDistancePulse {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 0.7; }
}
@keyframes miniZap {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 0.7; }
}

/* --- Card text compact ---------------------------------------------- */
.card-text-compact p {
  font-size: 0.85rem;
  line-height: 1.5;
}
.card-text-compact p + p {
  margin-top: 6px;
}

/* --- Experiment Timeline ---------------------------------------------- */
.timeline {
  position: relative;
  padding-left: 44px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--section-accent), transparent);
}

.timeline-item {
  position: relative;
  margin-bottom: 40px;
  padding: 24px 28px;
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  transition: var(--transition);
}

.timeline-item:hover {
  background: var(--bg-card-hover);
  transform: translateX(4px);
}

/* Timeline dot + type icon */
.timeline-item::before {
  content: '';
  position: absolute;
  left: -36px;
  top: 28px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--section-accent);
  box-shadow: 0 0 20px var(--section-accent);
  z-index: 2;
}

/* Type indicator ring behind the dot */
.timeline-item::after {
  content: '';
  position: absolute;
  left: -50px;
  top: 14px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid var(--section-accent);
  opacity: 0.06;
  pointer-events: none;
  z-index: 1;
  animation: timelineRing 4s ease-in-out infinite;
}

@keyframes timelineRing {
  0%, 100% { transform: scale(1); opacity: 0.06; }
  50% { transform: scale(1.15); opacity: 0.12; }
}

.timeline-year {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--section-accent);
  font-weight: 700;
  margin-bottom: 6px;
}

.timeline-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
  position: relative;
  display: inline-block;
}

/* Small gradient underline on timeline titles */
.timeline-title::after {
  content: '';
  position: absolute;
  bottom: -2px; left: 0;
  width: 100%; height: 1px;
  background: linear-gradient(90deg, var(--section-accent), transparent);
  opacity: 0.15;
}

.timeline-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.timeline-tag {
  display: inline-block;
  font-size: 0.7rem;
  padding: 2px 10px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--text-secondary);
  margin-top: 8px;
  font-family: var(--font-mono);
  position: relative;
  overflow: hidden;
}

/* Glow dot on timeline tag */
.timeline-tag::before {
  content: '';
  position: absolute;
  left: -6px; top: 50%;
  transform: translateY(-50%);
  width: 4px; height: 4px;
  border-radius: 50%;
  background: var(--section-accent);
  opacity: 0.3;
}

/* --- Interpretation Accordion ----------------------------------------- */
.interpretation {
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  margin-bottom: 16px;
  overflow: hidden;
  transition: var(--transition);
}

.interpretation:hover {
  border-color: rgba(255, 255, 255, 0.12);
}

.interpretation-header {
  padding: 20px 24px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.interpretation-header h3 {
  font-size: 1.05rem;
  margin: 0;
  display: flex;
  align-items: center;
  gap: 12px;
}

.interpretation-header .interp-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
  flex-shrink: 0;
}

.interpretation-toggle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  transition: var(--transition);
  flex-shrink: 0;
}

.interpretation.open .interpretation-toggle {
  transform: rotate(45deg);
}

.interpretation-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s ease, padding 0.3s ease;
  padding: 0 24px;
}

.interpretation.open .interpretation-body {
  max-height: 800px;
  padding: 0 24px 20px;
}

.interpretation-body p {
  font-size: 0.92rem;
  margin-bottom: 0.8rem;
}

.interpretation-body p:last-child {
  margin-bottom: 0;
}

/* --- Math / Formula Block --------------------------------------------- */
.formula-block {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 12px;
  padding: 28px 32px;
  margin: 24px 0;
  font-family: var(--font-mono);
  text-align: center;
  font-size: clamp(1rem, 2.5vw, 1.3rem);
  color: var(--section-accent);
  overflow-x: auto;
  position: relative;
}

/* Decorative math orbit ring */
.formula-block::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 12px;
  background: radial-gradient(ellipse at center, var(--section-accent), transparent);
  opacity: 0.03;
  pointer-events: none;
}

/* Decorative corner brackets */
.formula-block::after {
  content: '〈 〉';
  position: absolute;
  font-size: 2rem;
  color: var(--section-accent);
  opacity: 0.04;
  font-family: var(--font-mono);
  letter-spacing: 8px;
  bottom: 4px;
  right: 10px;
  pointer-events: none;
}

.formula-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 8px;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 2px;
  position: relative;
  z-index: 1;
}

/* --- Info Box --------------------------------------------------------- */
.info-box {
  background: rgba(0, 240, 255, 0.04);
  border: 1px solid rgba(0, 240, 255, 0.12);
  border-left: 3px solid var(--cyan);
  border-radius: 8px;
  padding: 20px 24px;
  margin: 20px 0;
  position: relative;
  overflow: hidden;
}

/* Decorative corner glow */
.info-box::before {
  content: '';
  position: absolute;
  top: -20px;
  right: -20px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--cyan), transparent);
  opacity: 0.06;
  pointer-events: none;
}

.info-box p {
  margin-bottom: 0;
  font-size: 0.92rem;
  position: relative;
  z-index: 1;
}

.info-box.warning {
  background: rgba(255, 102, 51, 0.04);
  border-color: rgba(255, 102, 51, 0.15);
  border-left-color: var(--orange);
}
.info-box.warning::before {
  background: radial-gradient(circle, var(--orange), transparent);
}

.info-box.idea {
  background: rgba(255, 215, 0, 0.04);
  border-color: rgba(255, 215, 0, 0.12);
  border-left-color: var(--gold);
}
.info-box.idea::before {
  background: radial-gradient(circle, var(--gold), transparent);
}

/* --- Quote Block ------------------------------------------------------ */
.quote-block {
  position: relative;
  padding: 32px 40px 32px 48px;
  margin: 32px 0;
  border-left: 3px solid var(--section-accent);
  background: rgba(255, 255, 255, 0.02);
  border-radius: 0 12px 12px 0;
  overflow: hidden;
}

/* Decorative giant quote mark */
.quote-block::before {
  content: '""';
  position: absolute;
  top: -10px;
  left: -6px;
  font-size: 6rem;
  font-family: Georgia, 'Times New Roman', serif;
  color: var(--section-accent);
  opacity: 0.04;
  line-height: 1;
  letter-spacing: -8px;
  pointer-events: none;
  user-select: none;
}

/* Decorative orbiting dots */
.quote-block::after {
  content: '';
  position: absolute;
  right: 16px;
  bottom: 12px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid var(--section-accent);
  opacity: 0.06;
  animation: quoteOrbit 6s linear infinite;
  pointer-events: none;
}

@keyframes quoteOrbit {
  0% { transform: rotate(0deg) translateX(4px) rotate(0deg); }
  100% { transform: rotate(360deg) translateX(4px) rotate(-360deg); }
}

/* Inner dot for orbiting ring */
.quote-block .quote-dot {
  display: none;
}

.quote-block blockquote {
  font-size: clamp(1rem, 2vw, 1.2rem);
  font-style: italic;
  color: var(--text-primary);
  line-height: 1.8;
  margin-bottom: 8px;
  position: relative;
  z-index: 1;
}

.quote-block cite {
  font-style: normal;
  font-size: 0.85rem;
  color: var(--section-accent);
  font-family: var(--font-mono);
  position: relative;
  z-index: 1;
}

/* --- Visualizations --------------------------------------------------- */
.entangled-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin: 40px auto;
  padding: 32px;
  background: rgba(0, 0, 0, 0.3);
  border-radius: 20px;
  border: 1px solid rgba(255, 255, 255, 0.05);
  max-width: 600px;
}

.particle {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: #fff;
  font-weight: 700;
  animation: pulse 3s ease-in-out infinite;
}

.particle-a {
  background: radial-gradient(circle at 35% 35%, var(--cyan), #0066aa);
  box-shadow: 0 0 40px rgba(0, 240, 255, 0.3);
}

.particle-b {
  background: radial-gradient(circle at 35% 35%, var(--magenta), #880055);
  box-shadow: 0 0 40px rgba(255, 0, 170, 0.3);
  animation-delay: 1.5s;
}

.particle-connector {
  display: flex;
  align-items: center;
  gap: 4px;
}

.particle-connector .line {
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--magenta));
  position: relative;
}

.particle-connector .line::after {
  content: '∞';
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  color: rgba(255, 255, 255, 0.3);
  font-size: 1.2rem;
}/* --- Double-Slit Experiment (v3 - big screen + clear interference) ---- */
.ds-container {
  margin: 32px auto;
  max-width: 900px;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(0, 240, 255, 0.1);
  border-radius: 16px;
  padding: 20px;
  position: relative;
  overflow: hidden;
}

.ds-mode-badge {
  text-align: center;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.ds-mode-text {
  display: inline-block;
  padding: 4px 16px;
  border-radius: 20px;
  background: rgba(0,240,255,0.08);
  border: 1px solid rgba(0,240,255,0.15);
  color: var(--cyan);
  transition: all 0.5s ease;
}

/* Badge stays the same color in both modes — only text changes */

/* Main experiment diagram (tall, screen takes right 35%) */
.ds-diagram {
  display: flex;
  align-items: stretch;
  height: 220px;
  gap: 0;
}

/* -- Source -- */
.ds-source {
  flex: 0 0 60px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
}

.ds-source-dot {
  width: 40px; height: 40px;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, var(--cyan), #004466);
  box-shadow: 0 0 40px rgba(0,240,255,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #fff;
  font-weight: 700;
  animation: dsSourcePulse 2s ease-in-out infinite;
}

.ds-source-arrow {
  margin-top: 4px;
  font-size: 0.8rem;
  color: rgba(0,240,255,0.25);
  animation: dsArrowMove 1.5s ease-in-out infinite;
}

/* -- Space before wall -- */
.ds-space {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
}

.ds-space::before {
  content: '';
  position: absolute;
  left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, rgba(0,240,255,0.2), transparent);
}

/* -- Wall with Slits -- */
.ds-wall {
  flex: 0 0 32px;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  position: relative;
  z-index: 2;
}

.ds-wall-block {
  background: rgba(200,210,230,0.08);
  border: 1px solid rgba(200,210,230,0.12);
}

.ds-wall-block.top { flex: 1; border-bottom: none; border-radius: 4px 4px 0 0; }
.ds-wall-block.mid { flex: 0 0 28px; border-top: none; border-bottom: none; }
.ds-wall-block.bot { flex: 1; border-top: none; border-radius: 0 0 4px 4px; }

.ds-slit-gap {
  flex: 0 0 22px;
  background: radial-gradient(ellipse at center, rgba(0,240,255,0.06), transparent);
  position: relative;
}

.ds-slit-gap::before {
  content: '▯';
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  font-size: 0.5rem;
  color: rgba(0,240,255,0.2);
}

/* -- After-wall zone (waves / particle lines) -- */
.ds-after {
  flex: 1.2;
  position: relative;
  overflow: hidden;
}

/* Wave rings (visible in wave mode) */
.ds-wave {
  position: absolute;
  border-radius: 50%;
  border: 1px solid rgba(0,240,255,0.03);
  animation: dsWaveExpand 3s ease-out infinite;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.6s ease;
}
.ds-container:not(.observed) .ds-wave { opacity: 1; }

.ds-wave.t1 { width: 8px; height: 8px; left: 15%; top: 26%; animation-delay: 0s; }
.ds-wave.t2 { width: 22px; height: 22px; left: 8%; top: 23%; animation-delay: 0.4s; }
.ds-wave.t3 { width: 38px; height: 38px; left: 1%; top: 20%; animation-delay: 0.8s; }
.ds-wave.t4 { width: 54px; height: 54px; left: -6%; top: 17%; animation-delay: 1.2s; }
.ds-wave.t5 { width: 72px; height: 72px; left: -14%; top: 14%; animation-delay: 1.6s; }

.ds-wave.b1 { width: 8px; height: 8px; left: 15%; top: 60%; animation-delay: 0.2s; }
.ds-wave.b2 { width: 22px; height: 22px; left: 8%; top: 57%; animation-delay: 0.6s; }
.ds-wave.b3 { width: 38px; height: 38px; left: 1%; top: 54%; animation-delay: 1s; }
.ds-wave.b4 { width: 54px; height: 54px; left: -6%; top: 51%; animation-delay: 1.4s; }
.ds-wave.b5 { width: 72px; height: 72px; left: -14%; top: 48%; animation-delay: 1.8s; }

/* Particle lines (visible when observed) */
.ds-particle-line {
  position: absolute;
  height: 1px;
  border-top: 1px dashed rgba(255,0,170,0.12);
  opacity: 0;
  transition: opacity 0.6s ease;
  pointer-events: none;
}
.ds-container.observed .ds-particle-line { opacity: 1; }

.ds-particle-line.top {
  width: 90%; top: 28%; left: 0;
  animation: dsLinePulse 2s ease-in-out infinite;
}
.ds-particle-line.bot {
  width: 90%; top: 60%; left: 0;
  animation: dsLinePulse 2s ease-in-out infinite 0.5s;
}

/* -- Screen (BIG! full height, 35% width) -- */
.ds-screen-wrap {
  flex: 1;
  display: flex;
  align-items: stretch;
  padding-left: 10px;
}

.ds-screen {
  width: 100%;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 3px;
  background: rgba(0,0,0,0.35);
  border-radius: 6px;
  border: 1px solid rgba(255,255,255,0.06);
  padding: 6px 4px;
  position: relative;
}

.ds-screen::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 2px;
  background: rgba(255,255,255,0.08);
  border-radius: 1px;
}

.ds-screen .ds-bar {
  width: 10px;
  min-width: 4px;
  border-radius: 4px 4px 0 0;
  background: linear-gradient(to top, rgba(0,240,255,0.65), rgba(0,240,255,0.04));
  transition: height 0.4s ease;
  flex-shrink: 1;
}

/* -- Labels -- */
.ds-labels {
  display: flex;
  align-items: center;
  padding: 0 4px;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 0.55rem;
  color: rgba(255,255,255,0.25);
}
.ds-labels .ds-label-source { flex: 0 0 60px; text-align: center; }
.ds-labels .ds-label-wall { flex: 0 0 32px; text-align: center; }
.ds-labels .ds-label-after { flex: 1.2; text-align: center; }
.ds-labels .ds-label-screen { flex: 1; text-align: center; }

@keyframes dsSourcePulse {
  0%, 100% { transform: scale(1); box-shadow: 0 0 30px rgba(0,240,255,0.4); }
  50% { transform: scale(1.08); box-shadow: 0 0 50px rgba(0,240,255,0.6); }
}

@keyframes dsArrowMove {
  0%, 100% { transform: translateX(0); opacity: 0.3; }
  50% { transform: translateX(6px); opacity: 0.6; }
}

@keyframes dsWaveExpand {
  0% { transform: scale(0.5); opacity: 0.3; border-color: rgba(0,240,255,0.08); }
  100% { transform: scale(3); opacity: 0; border-color: rgba(0,240,255,0); }
}

@keyframes dsLinePulse {
  0%, 100% { opacity: 0.15; }
  50% { opacity: 0.4; }
}

/* --- Buttons ---------------------------------------------------------- */
.btn {
  display: inline-block;
  padding: 12px 32px;
  border-radius: 50px;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: 2px solid var(--section-accent);
  color: var(--section-accent);
  background: transparent;
}

.btn:hover {
  background: var(--section-accent);
  color: var(--bg-deep);
  box-shadow: 0 0 40px var(--section-accent);
  transform: translateY(-2px);
}

/* --- Footer ----------------------------------------------------------- */
.site-footer {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 40px 24px 60px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* Decorative footer gradient bar */
.site-footer::before {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan), var(--magenta), transparent);
  opacity: 0.12;
}

/* Decorative quantum symbol in footer */
.site-footer::after {
  content: '⚛';
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.8rem;
  opacity: 0.08;
  pointer-events: none;
}

.site-footer p {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.25);
  margin: 0;
  position: relative;
  z-index: 1;
}

/* --- Scroll Reveal ---------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* --- Keyframes -------------------------------------------------------- */
/* --- CHSH Interactive Simulator ------------------------------------- */
.chsh-simulator {
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 16px;
  padding: 28px;
  margin: 32px auto;
  max-width: 600px;
}

.chsh-sliders {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px 24px;
  margin-bottom: 20px;
}

.chsh-slider-group label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.chsh-slider-group input[type="range"] {
  width: 100%;
  height: 4px;
  -webkit-appearance: none;
  appearance: none;
  background: rgba(255,255,255,0.1);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}

.chsh-slider-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--section-accent);
  cursor: pointer;
  box-shadow: 0 0 10px var(--section-accent);
}

.chsh-result {
  text-align: center;
  font-family: var(--font-mono);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--section-accent);
  margin-bottom: 12px;
}

.chsh-bar-container {
  margin-bottom: 8px;
}

.chsh-bar-bg {
  position: relative;
  height: 20px;
  background: rgba(255,255,255,0.05);
  border-radius: 10px;
  overflow: visible;
}

.chsh-bar-fill {
  height: 100%;
  border-radius: 10px;
  transition: width 0.2s ease;
  position: relative;
  z-index: 1;
}

.chsh-marker {
  position: absolute;
  top: -4px;
  width: 2px;
  height: 28px;
  background: rgba(255,255,255,0.4);
  transform: translateX(-50%);
  z-index: 2;
}

.chsh-marker span {
  position: absolute;
  top: -16px;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--text-secondary);
  white-space: nowrap;
}

.chsh-labels {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--text-secondary);
  margin-top: 4px;
}

.chsh-hint {
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-top: 12px;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), var(--magenta));
  z-index: 9999;
  transition: width 0.1s ease;
}

@keyframes fadeUp {
  to { opacity: 1; transform: translateY(0); }
  from { opacity: 0; transform: translateY(30px); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.9; }
  50% { transform: scale(1.08); opacity: 1; }
}

@keyframes bounce {
  0%, 100% { transform: rotate(45deg) translate(0, 0); }
  50% { transform: rotate(45deg) translate(4px, 4px); }
}

@keyframes dsExpand {
  0% { transform: scale(0.1); opacity: 0.5; }
  100% { transform: scale(3); opacity: 0; }
}

/* Bridge arrow between sections */
.bridge-arrow {
  position: relative;
  overflow: visible !important;
}

/* Decorative arrow pointing down → next section */
.bridge-arrow::after {
  content: '';
  position: absolute;
  bottom: -20px;
  left: 50%;
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--section-accent);
  border-bottom: 2px solid var(--section-accent);
  transform: translateX(-50%) rotate(45deg);
  opacity: 0.08;
  animation: bridgeBounce 2.5s ease-in-out infinite;
  pointer-events: none;
}

@keyframes bridgeBounce {
  0%, 100% { transform: translateX(-50%) rotate(45deg) translate(0, 0); opacity: 0.08; }
  50% { transform: translateX(-50%) rotate(45deg) translate(3px, 3px); opacity: 0.2; }
}

/* Decorative connecting dots on bridge sides */
.bridge-arrow::before {
  content: '';
  position: absolute;
  top: 50%;
  left: -8px;
  transform: translateY(-50%);
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--section-accent);
  opacity: 0.1;
  box-shadow: 0 0 8px var(--section-accent);
  animation: miniPulse 2s ease-in-out infinite;
}

/* Hero description subtle decoration */
.hero-description {
  position: relative;
}

.hero-description:first-of-type::after {
  content: '';
  position: absolute;
  bottom: -12px;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  opacity: 0.15;
}

/* --- Responsive ------------------------------------------------------- */
@media (max-width: 768px) {
  .section { padding: 60px 16px; }
  .section::before { width: 60%; }
  .quantum-nav { right: 12px; gap: 8px; }
  .quantum-nav a { width: 10px; height: 10px; }
  .card-grid { grid-template-columns: 1fr; }
  .timeline { padding-left: 28px; }
  .timeline-item::before { left: -24px; width: 8px; height: 8px; }
  .timeline-item::after { left: -36px; width: 28px; height: 28px; top: 18px; }
  .entangled-visual { flex-direction: column; gap: 12px; }
  .particle-connector { flex-direction: column; }
  .particle-connector .line { width: 2px; height: 30px; background: linear-gradient(180deg, var(--cyan), var(--magenta)); }
  .quote-block { padding: 20px 24px; }
  .formula-block { padding: 16px 20px; font-size: 0.85rem; }
  .ds-diagram { height: 110px; }
  .ds-source { flex: 0 0 50px; }
  .ds-source-dot { width: 28px; height: 28px; font-size: 0.6rem; }
  .ds-wall { flex: 0 0 28px; }
  .ds-wall-block.mid { flex: 0 0 18px; }
  .ds-slit-gap { flex: 0 0 14px; }
  .section-inner > p:not(.hero-description):not(.chsh-hint):not(.entangled-state-label) {
    padding-left: 10px;
  }
  .bridge-arrow::after {
    bottom: -14px;
    width: 14px;
    height: 14px;
  }
  .ds-after { display: none; }
  .ds-screen-wrap { flex: 1; }
  .ds-screen .ds-bar { width: 5px; min-width: 2px; }
  .ds-mode-badge { font-size: 0.65rem; }
  .ds-labels { font-size: 0.5rem; }
  .ds-labels .ds-label-source { flex: 0 0 50px; }
  .ds-labels .ds-label-wall { flex: 0 0 28px; }
}

/* --- Print ------------------------------------------------------------ */
@media print {
  #particles-canvas { display: none; }
  .quantum-nav { display: none; }
  .section { min-height: auto; padding: 40px 0; page-break-inside: avoid; }
  body { color: #000; background: #fff; }
  .card { border-color: #ddd; background: #fafafa; }
}