/**
 * 方案二：深色科技 — 暗色背景 + 青色点缀
 */
:root {
  --color-primary: #06b6d4;
  --color-accent: #22d3ee;
  --text-primary: #e2e8f0;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --bg-page: #0f1419;
  --bg-header: #1a2332;
  --bg-card: #1e293b;
  --bg-section-alt: #151d2b;
  --bg-banner: linear-gradient(135deg, #0c1929 0%, #134e4a 50%, #0e7490 100%);
  --bg-footer: #0c1929;
  --bg-nav-hover: rgba(6, 182, 212, 0.12);
  --bg-pill: rgba(6, 182, 212, 0.15);
  --bg-progress-track: #334155;
  --bg-video-placeholder: linear-gradient(135deg, #0f172a, #164e63);
  --border-light: #334155;
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
}

body.scheme-2 {
  background: var(--bg-page);
  color: var(--text-primary);
}

.scheme-2 .site-header:not(.portal-header) {
  box-shadow: 0 1px 0 rgba(6, 182, 212, 0.1);
}

.scheme-2 .portal-header {
  box-shadow: none;
}

.scheme-2 .btn-primary {
  background: linear-gradient(135deg, #0891b2, #06b6d4);
  box-shadow: 0 4px 14px rgba(6, 182, 212, 0.35);
}

.scheme-2 .btn-outline {
  background: transparent;
  border-color: var(--border-light);
  color: var(--text-primary);
}

.scheme-2 .site-logo {
  color: var(--color-primary);
  text-shadow: 0 0 20px rgba(6, 182, 212, 0.5);
}

.scheme-2 .index-card {
  background: rgba(6, 182, 212, 0.1);
  border-color: rgba(6, 182, 212, 0.2);
}

.scheme-2 .ai-rank-card .rank-badge.top3 {
  background: linear-gradient(135deg, #06b6d4, #0891b2);
}

.scheme-2 .report-card::before {
  background: linear-gradient(180deg, #06b6d4, #0891b2);
}