/* ============================================
   The Observer Hypothesis — Research Website
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- Reset & Base --- */
*, *::before, *::after {
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html {
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body {
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/* --- Typography --- */
h1, h2, h3, h4 {
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h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); }
h2 { font-size: clamp(1.8rem, 4vw, 2.8rem); margin-bottom: 1.5rem; }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.6rem); margin-bottom: 1rem; }

p {
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a {
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a:hover { opacity: 0.8; }

strong { color: var(--text-primary); font-weight: 600; }

/* --- Layout --- */
.section {
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}

.section-alt {
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}

.container {
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.container-wide {
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/* --- Fade-in Animation --- */
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.fade-in-delay-4 { transition-delay: 0.4s; }

/* --- Hero --- */
.hero {
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.hero h1 {
  margin-bottom: 1.5rem;
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.hero .subtitle {
  font-size: clamp(1.2rem, 2.5vw, 1.6rem);
  color: var(--text-secondary);
  margin-bottom: 1rem;
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}

.hero .tagline {
  font-size: 0.95rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 3rem;
}

.scroll-indicator {
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  display: flex;
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  gap: 8px;
  color: var(--text-muted);
  font-size: 0.8rem;
  animation: bounce 2s infinite;
}

.scroll-indicator svg {
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@keyframes bounce {
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  40% { transform: translateX(-50%) translateY(-8px); }
  60% { transform: translateX(-50%) translateY(-4px); }
}

/* --- Section Header --- */
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}

/* --- Highlight Box --- */
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  font-size: 1.1rem;
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}

/* --- Evidence List --- */
.evidence-list {
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  margin: 2rem 0;
}

.evidence-list li {
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  font-size: 1.05rem;
}

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}

.evidence-list .year {
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  font-size: 0.85rem;
  margin-right: 12px;
}

.evidence-list .author {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* --- Reasoning Chain --- */
.reasoning-chain {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 2rem 0;
}

.reasoning-chain li {
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  padding: 16px 0 16px 56px;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.reasoning-chain li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 14px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--accent-blue);
  color: var(--accent-blue);
  display: flex;
  align-items: center;
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  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
}

/* --- Architecture Diagram (SVG) --- */
.architecture-svg {
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  max-width: 700px;
  margin: 3rem auto;
  display: block;
}

/* --- Experiment Cards --- */
.experiment-grid {
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  gap: 20px;
  margin: 2.5rem 0;
}

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  border-radius: 12px;
  padding: 28px;
  transition: background 0.2s, border-color 0.2s;
}

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}

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  font-size: 0.75rem;
  color: var(--accent-blue);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

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  font-size: 1.15rem;
  margin-bottom: 8px;
}

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  color: var(--text-muted);
  margin-bottom: 12px;
}

.experiment-card .finding {
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  color: var(--text-secondary);
  line-height: 1.5;
}

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  font-size: 0.7rem;
  font-family: var(--font-mono);
  padding: 3px 10px;
  border-radius: 100px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 500;
}

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.badge-proposed { background: rgba(167, 139, 250, 0.15); color: var(--accent-purple); }

/* --- Results Section --- */
.result-stat {
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  align-items: baseline;
  gap: 12px;
  margin-bottom: 0.5rem;
}

.result-stat .number {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-blue);
  line-height: 1;
}

.result-stat .unit {
  font-size: 1rem;
  color: var(--text-muted);
}

.result-block {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: 12px;
  padding: 32px;
  margin: 2rem 0;
}

.result-block h3 {
  margin-bottom: 1rem;
}

.result-positive { border-left: 3px solid var(--accent-green); }
.result-negative { border-left: 3px solid var(--accent-red); }
.result-mixed { border-left: 3px solid var(--accent-amber); }

.figure-container {
  margin: 2.5rem 0;
  text-align: center;
}

.figure-container img {
  max-width: 100%;
  border-radius: 8px;
  border: 1px solid var(--border-card);
}

.figure-container .caption {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 12px;
  font-style: italic;
}

/* --- Quote Cards --- */
.quote-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: 2.5rem 0;
}

.quote-card {
  background: var(--bg-quote);
  border: 1px solid var(--border-card);
  border-radius: 10px;
  padding: 24px 28px;
}

.quote-card blockquote {
  font-size: 1.05rem;
  color: var(--text-primary);
  font-style: italic;
  line-height: 1.6;
  margin-bottom: 12px;
}

.quote-card .attribution {
  font-size: 0.85rem;
  color: var(--accent-purple);
  font-family: var(--font-mono);
}

/* --- Mapping Table --- */
.mapping-table {
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  border-collapse: collapse;
  margin: 2rem 0;
  font-size: 0.95rem;
}

.mapping-table th {
  text-align: left;
  padding: 14px 16px;
  background: var(--bg-card);
  color: var(--accent-blue);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 2px solid var(--border-card);
}

.mapping-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  vertical-align: top;
}

.mapping-table td:first-child {
  color: var(--text-primary);
  font-weight: 500;
  white-space: nowrap;
}

.mapping-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

/* --- Landscape Section --- */
.landscape-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 2.5rem 0;
}

.landscape-col {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: 12px;
  padding: 28px;
}

.landscape-col h3 {
  font-size: 1rem;
  margin-bottom: 16px;
}

.landscape-col.col-theory { border-top: 3px solid var(--accent-purple); }
.landscape-col.col-world-models { border-top: 3px solid var(--accent-amber); }
.landscape-col.col-us { border-top: 3px solid var(--accent-green); }

.landscape-col ul {
  list-style: none;
  padding: 0;
}

.landscape-col li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding: 6px 0;
}

/* --- Insight Cards --- */
.insight-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin: 2.5rem 0;
}

.insight-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: 12px;
  padding: 28px;
}

.insight-card .insight-number {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent-blue);
  opacity: 0.3;
  margin-bottom: 8px;
}

.insight-card h3 {
  font-size: 1.1rem;
  margin-bottom: 12px;
}

.insight-card p {
  font-size: 0.95rem;
  margin-bottom: 0;
}

/* --- Roadmap Cards --- */
.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin: 2.5rem 0;
}

.roadmap-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: 12px;
  padding: 28px;
  position: relative;
  overflow: hidden;
}

.roadmap-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
}

.roadmap-card .exp-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-purple);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.roadmap-card h3 {
  font-size: 1.1rem;
  margin-bottom: 12px;
}

.roadmap-card .question {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.roadmap-card .prediction {
  font-size: 0.85rem;
  color: var(--accent-teal);
  font-family: var(--font-mono);
}

/* --- About Section --- */
.about-content {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.about-text {
  flex: 1;
}

.about-links {
  display: flex;
  gap: 16px;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

.about-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border: 1px solid var(--border-card);
  border-radius: 8px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  transition: border-color 0.2s, color 0.2s;
}

.about-link:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  opacity: 1;
}

/* --- Footer --- */
.footer {
  padding: 60px 24px;
  text-align: center;
  border-top: 1px solid var(--border-subtle);
}

.footer p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.footer a {
  color: var(--text-secondary);
}

/* --- Nav --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(10, 10, 26, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-subtle);
  opacity: 0;
  transform: translateY(-100%);
  transition: opacity 0.3s, transform 0.3s;
}

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

.nav-brand {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--text-primary);
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-links a {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.nav-links a:hover {
  color: var(--text-primary);
  opacity: 1;
}

/* --- Callout --- */
.callout {
  background: linear-gradient(135deg, rgba(74, 158, 255, 0.08), rgba(167, 139, 250, 0.08));
  border: 1px solid rgba(74, 158, 255, 0.2);
  border-radius: 12px;
  padding: 32px;
  margin: 3rem 0;
  text-align: center;
}

.callout p {
  font-size: 1.15rem;
  color: var(--text-primary);
  margin-bottom: 0;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .section {
    padding: 60px 20px;
  }

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

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

  .nav-links {
    display: none;
  }

  .about-content {
    flex-direction: column;
  }

  .mapping-table {
    font-size: 0.8rem;
  }

  .mapping-table td:first-child {
    white-space: normal;
  }

  h1 {
    font-size: 2.2rem;
  }
}

@media (max-width: 480px) {
  .insight-grid,
  .roadmap-grid {
    grid-template-columns: 1fr;
  }
}