/* ==================================================
   04 — EXPLORE (Interactive Mathematical Experiments)
   ================================================== */
.section-explore {
  padding: var(--section-padding-y) 0;
  background-color: var(--bg-surface);
  position: relative;
  border-top: 1px solid var(--border-subtle);
}

.explore-header {
  margin-bottom: 4.5rem;
}

.explore-headline {
  font-size: clamp(2.5rem, 5vw, 4.25rem);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 1.25rem;
}

.explore-supporting {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
}

.explore-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
  gap: 2.5rem;
}

.experiment-card {
  background: var(--bg-primary);
  border: 1px solid var(--border-subtle);
  border-radius: 20px;
  padding: 2.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 520px;
  position: relative;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.experiment-card:hover {
  border-color: var(--border-teal);
  box-shadow: var(--shadow-md);
}

.experiment-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.experiment-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.experiment-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-teal);
  background: var(--accent-teal-subtle);
  padding: 0.25rem 0.6rem;
  border-radius: 4px;
}

/* Experiment 1: Interactive Angles */
.angle-stage {
  width: 100%;
  height: 220px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-surface);
  border-radius: 12px;
  border: 1px solid var(--border-subtle);
  margin-bottom: 1.5rem;
  position: relative;
}

.angle-svg {
  width: 90%;
  height: 90%;
}

.angle-controls {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.angle-slider-wrapper {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.angle-range-input {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: var(--border-strong);
  border-radius: 3px;
  outline: none;
  transition: background 0.3s ease;
}

.angle-range-input::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent-teal);
  cursor: pointer;
  box-shadow: 0 2px 8px var(--accent-teal-glow);
  border: 2px solid #FFFFFF;
  transition: transform 0.2s ease;
}

.angle-range-input::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

.angle-degree-badge {
  font-family: var(--font-mono);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--accent-yellow);
  min-width: 54px;
  text-align: right;
}

/* Experiment 2: Interactive Probability */
.probability-stage {
  width: 100%;
  height: 220px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--bg-surface);
  border-radius: 12px;
  border: 1px solid var(--border-subtle);
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
}

.probability-tokens-row {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.prob-token {
  width: 46px;
  height: 46px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.1rem;
  transition: transform 0.4s var(--transition-bounce), background-color 0.3s ease;
  border: 1px solid var(--border-subtle);
  background: var(--bg-primary);
}

.prob-token.highlighted {
  background: var(--accent-yellow);
  color: #121214;
  border-color: var(--border-yellow);
  transform: scale(1.15) translateY(-4px);
  box-shadow: 0 8px 16px var(--accent-yellow-glow);
}

.prob-stats {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  display: flex;
  gap: 1.5rem;
}

.btn-try-again {
  width: 100%;
  padding: 0.85rem 1.5rem;
  background: var(--accent-teal);
  color: #FFFFFF;
  border: none;
  border-radius: 8px;
  font-family: var(--font-main);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  letter-spacing: 0.05em;
  transition: all 0.3s ease;
  margin-bottom: 1.25rem;
}

.btn-try-again:hover {
  background: #0D9488;
  transform: translateY(-2px);
  box-shadow: 0 6px 18px var(--accent-teal-glow);
}

/* Experiment 3: Interactive Fractions */
.fraction-stage {
  width: 100%;
  height: 220px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-surface);
  border-radius: 12px;
  border: 1px solid var(--border-subtle);
  margin-bottom: 1.5rem;
  position: relative;
}

.fraction-svg {
  width: 170px;
  height: 170px;
  overflow: visible;
}

.fraction-controls {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.fraction-slider-wrapper {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.fraction-buttons-row {
  display: flex;
  justify-content: space-between;
  gap: 0.5rem;
}

.fraction-btn {
  flex: 1;
  padding: 0.4rem 0;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.fraction-btn.active, .fraction-btn:hover {
  background: var(--accent-blue);
  color: #FFFFFF;
  border-color: var(--accent-blue);
}

.experiment-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==================================================
   10 — BIG INTERACTIVE GRID
   ================================================== */
.section-big-grid {
  position: relative;
  min-height: 100vh;
  width: 100%;
  background-color: #F8F6F2;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  border-top: 1px solid var(--border-subtle);
}

.big-grid-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

.big-grid-content {
  position: relative;
  z-index: 5;
  text-align: center;
  pointer-events: none;
  max-width: 800px;
  padding: 2rem;
}

.big-grid-hint {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--accent-blue);
  margin-bottom: 1.5rem;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(8px);
  display: inline-block;
  padding: 0.4rem 1.2rem;
  border-radius: 999px;
  border: 1px solid var(--border-blue);
}

.big-grid-headline-1 {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
  color: var(--text-primary);
}

.big-grid-headline-2 {
  font-size: clamp(2rem, 4vw, 3.5rem);
  font-weight: 600;
  color: var(--text-secondary);
  opacity: 0.85;
}

.big-grid-coords-hud {
  position: absolute;
  bottom: 2rem;
  right: 2rem;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 0.75rem 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  z-index: 6;
  box-shadow: var(--shadow-sm);
  pointer-events: none;
}

.big-grid-coords-hud span {
  color: var(--accent-yellow);
  font-weight: 700;
}