:root {
  /* Brand */
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --primary-subtle: #eef2ff;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
  --accent: #06b6d4;

  /* Semantic backgrounds */
  --success-bg: rgba(16, 185, 129, 0.1);
  --warning-bg: rgba(245, 158, 11, 0.1);
  --danger-bg: rgba(239, 68, 68, 0.1);
  --info-bg: rgba(59, 130, 246, 0.1);
  --bg-nested: var(--surface-hover);

  /* Surfaces */
  --background: #f8fafc;
  --surface: #ffffff;
  --surface-elevated: #ffffff;
  --surface-hover: #f1f5f9;
  --surface-active: #e2e8f0;
  --border: #e2e8f0;
  --border-subtle: #f1f5f9;

  /* Text */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --text-inverse: #ffffff;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.03), 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.04), 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 12px 20px rgba(0, 0, 0, 0.05), 0 4px 8px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 24px 32px rgba(0, 0, 0, 0.06), 0 8px 16px rgba(0, 0, 0, 0.04);

  /* Typography */
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', ui-monospace, 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-size-4xl: 2.25rem;

  /* Line heights */
  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.625rem;
  --radius-lg: 0.875rem;
  --radius-xl: 1.125rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Layout */
  --header-height: 56px;
  --nav-width: 220px;
  --transition: 180ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 250ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Breakpoints */
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
}

[data-theme='light'] {
  /* Brand */
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --primary-subtle: #eef2ff;
  --accent: #06b6d4;

  /* Surfaces */
  --background: #f8fafc;
  --surface: #ffffff;
  --surface-elevated: #ffffff;
  --surface-hover: #f1f5f9;
  --surface-active: #e2e8f0;
  --border: #e2e8f0;
  --border-subtle: #f1f5f9;

  /* Text */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --text-inverse: #ffffff;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.03), 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.04), 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 12px 20px rgba(0, 0, 0, 0.05), 0 4px 8px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 24px 32px rgba(0, 0, 0, 0.06), 0 8px 16px rgba(0, 0, 0, 0.04);
}

[data-theme='dark'] {
  /* Brand */
  --primary: #818cf8;
  --primary-hover: #a5b4fc;
  --primary-subtle: rgba(129, 140, 248, 0.12);
  --accent: #22d3ee;

  /* Surfaces */
  --background: #0b1120;
  --surface: #111827;
  --surface-elevated: #1e293b;
  --surface-hover: #1e293b;
  --surface-active: #334155;
  --border: #1e293b;
  --border-subtle: #172033;

  /* Text */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-inverse: #0b1120;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.2), 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.2), 0 2px 4px rgba(0, 0, 0, 0.25);
  --shadow-lg: 0 12px 20px rgba(0, 0, 0, 0.25), 0 4px 8px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 24px 32px rgba(0, 0, 0, 0.35), 0 8px 16px rgba(0, 0, 0, 0.25);
}