:root {
  /* Colors */
  --color-primary: #1e3a5f;
  --color-primary-light: #2d5a8e;
  --color-primary-dark: #152a45;
  --color-secondary: #2ecc71;
  --color-secondary-dark: #27ae60;
  --color-accent: #e74c3c;
  --color-bg: #ffffff;
  --color-bg-alt: #f8f9fa;
  --color-bg-card: #ffffff;
  --color-text: #2c3e50;
  --color-text-muted: #6c757d;
  --color-text-inverse: #ffffff;
  --color-border: #dee2e6;
  --color-border-light: #e9ecef;
  --color-success: #28a745;
  --color-warning: #ffc107;
  --color-error: #dc3545;
  --color-info: #17a2b8;
  --color-highlight: #fff3cd;

  /* Spacing (8px base) */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Typography */
  --font-body: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: ui-monospace, 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  --text-sm: clamp(0.875rem, 0.8rem + 0.25vw, 1rem);
  --text-base: clamp(1rem, 0.9rem + 0.35vw, 1.125rem);
  --text-lg: clamp(1.25rem, 1.1rem + 0.5vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 0.8vw, 2rem);
  --text-2xl: clamp(1.875rem, 1.4rem + 1.2vw, 2.5rem);
  --text-3xl: clamp(2.25rem, 1.6rem + 1.6vw, 3rem);

  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;

  /* Layout */
  --max-width: 1200px;
  --max-content: 75ch;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-primary: #4a9eff;
    --color-primary-light: #6db3ff;
    --color-primary-dark: #2d7dd2;
    --color-secondary: #2ecc71;
    --color-secondary-dark: #27ae60;
    --color-bg: #1a1a2e;
    --color-bg-alt: #16213e;
    --color-bg-card: #1f2940;
    --color-text: #e0e0e0;
    --color-text-muted: #a0a0a0;
    --color-text-inverse: #1a1a2e;
    --color-border: #2d3748;
    --color-border-light: #374151;
    --color-highlight: #3d3200;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.4);
  }
}

[data-theme="dark"] {
  --color-primary: #4a9eff;
  --color-primary-light: #6db3ff;
  --color-primary-dark: #2d7dd2;
  --color-secondary: #2ecc71;
  --color-secondary-dark: #27ae60;
  --color-bg: #1a1a2e;
  --color-bg-alt: #16213e;
  --color-bg-card: #1f2940;
  --color-text: #e0e0e0;
  --color-text-muted: #a0a0a0;
  --color-text-inverse: #1a1a2e;
  --color-border: #2d3748;
  --color-border-light: #374151;
  --color-highlight: #3d3200;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.4);
}