[data-theme="dark"] {
  --color-bg: #1A1A2E;
  --color-bg-card: #16213E;
  --color-bg-header: #0F3460;
  --color-text: #E8E8E8;
  --color-text-secondary: #A0A0B0;
  --color-text-muted: #6B6B80;
  --color-border: #2A2A4A;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --color-shadow-hover: rgba(0, 0, 0, 0.4);
  --color-overlay: rgba(0, 0, 0, 0.7);
}
[data-theme="dark"] .header {
  background-color: rgba(15, 52, 96, 0.85);
}
[data-theme="dark"] .nav-item.active {
  background-color: rgba(108, 99, 255, 0.2);
}