/**
 * Luxury Marble — glossy black/white stone with metal accents.
 */
[data-theme="luxury_marble"] {
  --cp-bg: #121214;
  --cp-fg: #f8f7f4;
  --cp-surface: #1c1c20;
  --cp-border: #4a4a52;
  --cp-muted: #a8a8b0;
  --cp-accent: #c0a060;
  --cp-accent-soft: rgba(192, 160, 96, 0.2);
  --cp-input-bg: #0e0e10;
  --cp-square-light: #f2f0ea;
  --cp-square-dark: #2a2a2e;
  --cp-board-shadow: 0 12px 36px rgba(0, 0, 0, 0.5), inset 0 0 0 1px rgba(255, 255, 255, 0.08);
  --cp-piece-filter: contrast(1.05);
}