/* han-dan-xue-bu — 成语系列水彩主题（柔青蓝） */
:root {
  --story-bg: #00695c;
  --story-primary: #80deea;
  --story-accent: #26a69a;
  --story-gradient: linear-gradient(180deg, #00695c 0%, #26a69a 55%, #b2ebf2 100%);
  --story-card-bg: rgba(255, 255, 255, 0.08);
  --story-text: #e0f7fa;
  --story-text-secondary: rgba(224, 247, 250, 0.72);
  --story-glow: 0 0 30px rgba(255, 255, 255, 0.2);
}

body {
  background: var(--story-bg);
  color: var(--story-text);
}

.btn-primary {
  background: linear-gradient(135deg, #80deea, #00897b);
  color: #004d40;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25);
}

.choice-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 2px solid rgba(255, 255, 255, 0.22);
}
.choice-btn:hover {
  border-color: #80deea;
  box-shadow: 0 0 18px rgba(255, 255, 255, 0.15);
}

.confirm-overlay {
  background: rgba(0, 0, 0, 0.88);
}
.confirm-card {
  border: 2px solid rgba(255, 255, 255, 0.18);
}

.knowledge-card {
  border-left: 3px solid #80deea;
}

.parent-hint-toggle {
  color: #80deea;
}