/* ═══════════════════════════════════════════
   CONTEXT COLLAPSE — BTA DARK MODE STYLES
   ═══════════════════════════════════════════ */

:root {
  /* Dark Mode Palette */
  --bg: #0a0a0a;
  --card: #111111;
  --border: #1f1f1f;
  --border-hover: #333333;
  --text: #e5e5e5;
  --text-muted: #737373;
  --text-subtle: #525252;

  /* Semantic Colors */
  --green: #22C55E;
  --green-rgb: 34, 197, 94;
  --red: #EF4444;
  --red-rgb: 239, 68, 68;
  --amber: #F59E0B;
  --amber-rgb: 245, 158, 11;
  --blue: #3B82F6;
  --blue-rgb: 59, 130, 246;

  /* Typography */
  --mono: 'SF Mono', 'Fira Code', 'Cascadia Code', ui-monospace, monospace;
  --sans: system-ui, -apple-system, Segoe UI, Roboto, sans-serif;

  /* Layout */
  --radius: 8px;
  --card-min-width: 420px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--mono);
  overflow-x: hidden;
}

/* ═══ HEADER ═══ */
header {
  text-align: center;
  padding: 48px 24px 32px;
  border-bottom: 1px solid var(--border);
}

header h1 {
  font-size: 1.6rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: #f5f5f5;
}

header p {
  margin-top: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ═══ DEFINITION SECTION ═══ */
.definition-section {
  max-width: 800px;
  margin: 0 auto;
  padding: 48px 24px;
  text-align: center;
}

.definition {
  font-size: 1.05rem;
  font-style: italic;
  color: var(--text);
  line-height: 1.7;
  border-left: 3px solid var(--amber);
  padding-left: 24px;
  text-align: left;
  margin: 0 0 24px 0;
}

.definition-note {
  font-size: 0.85rem;
  color: var(--amber);
  letter-spacing: 0.02em;
}

.definition-ai {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

/* ═══ CATEGORY SECTIONS ═══ */
.category-section {
  max-width: 1600px;
  margin: 0 auto;
  padding: 48px 24px 16px;
  border-top: 1px solid var(--border);
}

.category-title {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--text);
  letter-spacing: 0.02em;
  margin-bottom: 8px;
}

.category-subtitle {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 28px;
}

/* ═══ CARD GRID ═══ */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(var(--card-min-width), 1fr));
  gap: 24px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.2s, transform 0.2s;
  cursor: pointer;
}

.card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
}

.card-canvas {
  width: 100%;
  height: 280px;
  position: relative;
  overflow: hidden;
  background: #050505;
}

.card-canvas iframe {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}

.card-info {
  padding: 16px;
  border-top: 1px solid var(--border);
}

.card-symptom {
  font-size: 0.8rem;
  font-style: italic;
  color: #a3a3a3;
  line-height: 1.5;
  margin-bottom: 8px;
}

.card-frustration {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 10px;
}

.card-title {
  font-size: 0.7rem;
  font-weight: 400;
  color: var(--text-subtle);
  text-align: right;
  letter-spacing: 0.04em;
}

/* ═══ FULLSCREEN OVERLAY ═══ */
.overlay {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 100;
  background: #050505;
}

.overlay.active {
  display: flex;
  flex-direction: column;
}

.overlay-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.overlay-header h2 {
  font-size: 1rem;
  font-weight: 500;
}

.overlay-close {
  background: var(--border);
  border: 1px solid var(--border-hover);
  color: var(--text);
  padding: 6px 16px;
  border-radius: 4px;
  font-family: inherit;
  font-size: 0.8rem;
  cursor: pointer;
  transition: background 0.2s;
}

.overlay-close:hover {
  background: #262626;
}

.overlay-canvas {
  flex: 1;
  background: #050505;
}

.overlay-canvas iframe {
  width: 100%;
  height: 100%;
  border: none;
}

/* ═══ BLIND SPOTS SECTION ═══ */
.blindspots-section {
  max-width: 1200px;
  margin: 0 auto;
  padding: 64px 24px;
  border-top: 1px solid var(--border);
}

.blindspots-title {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--text);
  text-align: center;
  margin-bottom: 8px;
}

.blindspots-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 40px;
}

.blindspots-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.blindspot {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.blindspot-icon {
  font-size: 0.7rem;
  color: var(--amber);
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.blindspot h3 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

.blindspot p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ═══ FOOTER ═══ */
footer {
  text-align: center;
  padding: 48px 24px 32px;
  border-top: 1px solid var(--border);
}

.footer-cta {
  margin-bottom: 24px;
}

.footer-cta p {
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 12px;
}

.cta-link {
  display: inline-block;
  font-size: 0.9rem;
  color: var(--bg);
  background: var(--green);
  padding: 12px 28px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 500;
  transition: opacity 0.2s, transform 0.2s;
}

.cta-link:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

.footer-copyright {
  color: var(--text-subtle);
  font-size: 0.75rem;
}

.footer-copyright a {
  color: var(--text-muted);
  text-decoration: none;
}

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

/* ═══ RESPONSIVE ═══ */
@media (max-width: 900px) {
  :root {
    --card-min-width: 340px;
  }
}

@media (max-width: 500px) {
  :root {
    --card-min-width: 100%;
  }

  .grid {
    gap: 16px;
  }

  .category-section {
    padding: 32px 16px 8px;
  }

  .category-title {
    font-size: 1.1rem;
  }

  header {
    padding: 32px 16px 24px;
  }

  header h1 {
    font-size: 1.2rem;
  }

  .card-canvas {
    height: 220px;
  }

  .definition-section {
    padding: 32px 16px;
  }

  .definition {
    font-size: 0.95rem;
    padding-left: 16px;
  }

  .blindspots-section {
    padding: 40px 16px;
  }

  .blindspots-grid {
    gap: 16px;
  }

  .blindspot {
    padding: 20px;
  }
}