:root {
  /* Brand colours */
  --color-primary: #0f4c81;
  --color-primary-dark: #0a3560;
  --color-primary-light: #1a6db5;
  --color-accent: #f4a300;
  --color-accent-dark: #c98a00;

  /* Neutrals */
  --color-bg: #ffffff;
  --color-bg-subtle: #f8f9fa;
  --color-bg-muted: #e9ecef;
  --color-border: #dee2e6;
  --color-border-strong: #adb5bd;

  /* Text */
  --color-text: #212529;
  --color-text-muted: #6c757d;
  --color-text-inverse: #ffffff;

  /* Status */
  --color-success: #198754;
  --color-warning: #ffc107;
  --color-danger: #dc3545;
  --color-info: #0dcaf0;

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  --font-size-base: 1rem;
  --font-size-sm: 0.875rem;
  --font-size-lg: 1.125rem;
  --line-height-base: 1.6;

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

  /* Borders */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.10);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);

  /* Layout */
  --container-max: 1200px;
  --nav-height: 64px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg: #0d1117;
    --color-bg-subtle: #161b22;
    --color-bg-muted: #21262d;
    --color-border: #30363d;
    --color-border-strong: #484f58;
    --color-text: #e6edf3;
    --color-text-muted: #8b949e;
    --color-text-inverse: #0d1117;
    --color-primary: #58a6ff;
    --color-primary-dark: #388bfd;
    --color-primary-light: #79b8ff;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  }
}

:root[data-theme="dark"] {
  --color-bg: #0d1117;
  --color-bg-subtle: #161b22;
  --color-bg-muted: #21262d;
  --color-border: #30363d;
  --color-border-strong: #484f58;
  --color-text: #e6edf3;
  --color-text-muted: #8b949e;
  --color-text-inverse: #0d1117;
  --color-primary: #58a6ff;
  --color-primary-dark: #388bfd;
  --color-primary-light: #79b8ff;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
}