:root {
  /* === Color Palette === */
  --color-bg-primary: #0a0a0f;
  --color-bg-secondary: #12121a;
  --color-bg-tertiary: #1a1a2e;
  --color-bg-card: rgba(255, 255, 255, 0.04);

  /* Glass */
  --glass-bg: rgba(255, 255, 255, 0.05);
  --glass-bg-hover: rgba(255, 255, 255, 0.08);
  --glass-border: rgba(255, 255, 255, 0.1);
  --glass-blur: blur(20px);

  /* Accent */
  --color-accent: #3b82f6;
  --color-accent-hover: #2563eb;
  --color-accent-glow: rgba(59, 130, 246, 0.3);
  --color-accent-subtle: rgba(59, 130, 246, 0.1);

  /* Semantic */
  --color-success: #10b981;
  --color-success-subtle: rgba(16, 185, 129, 0.1);
  --color-warning: #f59e0b;
  --color-warning-subtle: rgba(245, 158, 11, 0.1);
  --color-error: #ef4444;
  --color-error-subtle: rgba(239, 68, 68, 0.1);
  --color-info: #06b6d4;

  /* Text */
  --color-text-primary: #f1f5f9;
  --color-text-secondary: #94a3b8;
  --color-text-muted: #64748b;
  --color-text-inverse: #0a0a0f;

  /* Borders */
  --color-border: rgba(255, 255, 255, 0.08);
  --color-border-focus: rgba(59, 130, 246, 0.5);

  /* === Spacing (4px base) === */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;

  /* === Typography === */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;

  /* === Border Radius === */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* === Shadows === */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 20px var(--color-accent-glow);

  /* === Transitions === */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms cubic-bezier(0.16, 1, 0.3, 1);

  /* === Z-index === */
  --z-base: 0;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-overlay: 300;
  --z-modal: 400;
  --z-toast: 500;

  /* === Safe areas === */
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
  --safe-right: env(safe-area-inset-right, 0px);

  /* === Layout === */
  --header-height: 56px;
  --bottom-bar-height: 64px;
  --content-max-width: 480px;
}
