/* AI Digital Human Section */
.ai-section { background: var(--bg-secondary); position: relative; overflow: hidden; }
.ai-section::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(ellipse at 50% 50%, rgba(201,168,76,0.05) 0%, transparent 70%);
}
.ai-content { position: relative; z-index: 1; }
.ai-demo-wrap {
  display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
}
.ai-screen {
  aspect-ratio: 16/10; background: var(--bg-primary); border-radius: var(--radius-lg);
  border: 2px solid var(--border-color); display: flex; flex-direction: column;
  align-items: center; justify-content: center; position: relative; overflow: hidden;
}
.ai-screen::before {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(201,168,76,0.05), transparent);
}
.ai-avatar-placeholder {
  font-size: 5rem; margin-bottom: 16px; position: relative; z-index: 1;
}
.ai-status {
  display: flex; align-items: center; gap: 8px; font-size: 0.85rem;
  color: var(--success); position: relative; z-index: 1;
}
.ai-status::before {
  content: ''; width: 8px; height: 8px; border-radius: 50%;
  background: var(--success); animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.5); }
}
.ai-topics { display: flex; flex-direction: column; gap: 12px; }
.ai-topic {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-md); padding: 16px 20px; transition: var(--transition);
  cursor: pointer; display: flex; align-items: center; gap: 12px;
}
.ai-topic:hover { border-color: var(--accent); background: var(--bg-card-hover); }
.ai-topic-icon { font-size: 1.5rem; }
.ai-topic-text { font-size: 0.9rem; line-height: 1.4; }
.ai-features {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 60px;
}
.ai-feature {
  text-align: center; padding: 32px 20px; background: var(--bg-card);
  border-radius: var(--radius-lg); border: 1px solid var(--border-color);
  transition: var(--transition);
}
.ai-feature:hover { border-color: var(--accent); }
.ai-feature-icon { font-size: 2.5rem; margin-bottom: 16px; }
.ai-feature h4 { font-size: 1rem; margin-bottom: 8px; }
.ai-feature p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5; }

/* Course Section */
.course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 24px; }
.course-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-lg); overflow: hidden; transition: var(--transition);
}
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--border-light); }
.course-thumb { aspect-ratio: 16/9; background: var(--bg-secondary); display: flex; align-items: center; justify-content: center; font-size: 3rem; }
.course-body { padding: 24px; }
.course-body h4 { font-size: 1rem; margin-bottom: 8px; }
.course-body p { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 16px; }
.course-meta { display: flex; justify-content: space-between; align-items: center; }
.course-price { font-weight: 700; color: var(--accent); }
.course-lessons { font-size: 0.8rem; color: var(--text-muted); }