:root {
  /* Brand */
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-subtle: #eef2ff;
  --success: #059669;
  --warning: #d97706;
  --danger: #dc2626;
  --info: #2563eb;
  --accent: #06b6d4;

  /* Semantic backgrounds */
  --success-bg: rgba(5, 150, 105, 0.1);
  --warning-bg: rgba(217, 119, 6, 0.1);
  --danger-bg: rgba(220, 38, 38, 0.1);
  --info-bg: rgba(37, 99, 235, 0.1);
  --bg-nested: var(--surface-hover);

  /* Surfaces */
  --background: #fafafa;
  --surface: #ffffff;
  --surface-elevated: #ffffff;
  --surface-hover: #f5f5f5;
  --surface-active: #ebebeb;
  --border: #e5e5e5;
  --border-subtle: #f0f0f0;

  /* Text */
  --text-primary: #171717;
  --text-secondary: #525252;
  --text-muted: #737373;
  --text-inverse: #ffffff;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.04), 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.04), 0 4px 6px rgba(0, 0, 0, 0.06);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.06), 0 8px 10px rgba(0, 0, 0, 0.04);

  /* Typography */
  --font-family: 'Inter', 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: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Layout */
  --header-height: 56px;
  --nav-width: 220px;
  --transition: 150ms ease;
  --transition-slow: 200ms ease;

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

[data-theme='light'] {
  /* Brand */
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-subtle: #eef2ff;
  --accent: #06b6d4;

  /* Surfaces */
  --background: #f5f5f5;
  --surface: #ffffff;
  --surface-elevated: #ffffff;
  --surface-hover: #f0f0f0;
  --surface-active: #e5e5e5;
  --border: #e5e5e5;
  --border-subtle: #f0f0f0;

  /* Text */
  --text-primary: #171717;
  --text-secondary: #525252;
  --text-muted: #737373;
  --text-inverse: #ffffff;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.04), 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.04), 0 4px 6px rgba(0, 0, 0, 0.06);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.06), 0 8px 10px rgba(0, 0, 0, 0.04);
}

[data-theme='dark'] {
  /* Brand */
  --primary: #6366f1;
  --primary-hover: #818cf8;
  --primary-subtle: rgba(99, 102, 241, 0.12);
  --accent: #22d3ee;

  /* Surfaces */
  --background: #0a0a0a;
  --surface: #141414;
  --surface-elevated: #1a1a1a;
  --surface-hover: #262626;
  --surface-active: #333333;
  --border: #262626;
  --border-subtle: #1f1f1f;

  /* Text */
  --text-primary: #fafafa;
  --text-secondary: #a3a3a3;
  --text-muted: #737373;
  --text-inverse: #0a0a0a;

  /* Shadows */
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.24), 0 1px 3px rgba(0, 0, 0, 0.32);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.24), 0 2px 4px rgba(0, 0, 0, 0.32);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.32), 0 4px 6px rgba(0, 0, 0, 0.24);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.4), 0 8px 10px rgba(0, 0, 0, 0.32);
}