:root {
  color-scheme: dark;

  /* Color */
  --color-canvas: #050505;
  --color-surface: #0d0d0d;
  --color-surface-raised: #151515;
  --color-surface-inverse: #f5f5f2;
  --color-text: #f5f5f2;
  --color-text-soft: #b8b8b3;
  --color-text-muted: #92928d;
  --color-text-inverse: #080808;
  --color-border-subtle: #242424;
  --color-border: #3a3a3a;
  --color-border-strong: #70706b;
  --color-highlight: #ffffff;
  --color-focus: #ffffff;

  /* Backward-compatible aliases used by existing page styles. */
  --color-grid: var(--color-border-subtle);
  --color-inverse: var(--color-text-inverse);

  /* Typography */
  --font-display: "Helvetica Neue", Arial, system-ui, sans-serif;
  --font-body: system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Consolas, monospace;
  --font-size-2xs: 0.6875rem;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: clamp(1.5rem, 2vw, 2rem);
  --font-size-2xl: clamp(2rem, 4vw, 4rem);
  --font-size-display: clamp(3.25rem, 8vw, 7.75rem);
  --font-weight-regular: 400;
  --font-weight-medium: 550;
  --font-weight-semibold: 650;
  --font-weight-bold: 750;
  --line-height-tight: 0.92;
  --line-height-heading: 1.05;
  --line-height-body: 1.6;
  --line-height-loose: 1.75;
  --letter-spacing-tight: -0.055em;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.08em;
  --letter-spacing-label: 0.14em;

  /* Spacing */
  --space-0: 0;
  --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;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-section: clamp(4rem, 9vw, 8rem);

  /* Layout */
  --container-text: 42rem;
  --container-form: 48rem;
  --container-content: 80rem;
  --content-width: var(--container-content);
  --gutter: clamp(1rem, 3vw, 1.5rem);

  /* Geometry */
  --border-width-hairline: 1px;
  --border-width-focus: 2px;
  --border-width-emphasis: 3px;
  --radius-none: 0;
  --radius-xs: 2px;
  --radius-sm: 4px;
  --radius-md: 8px;

  /* Depth */
  --shadow-none: none;
  --shadow-panel: 0 20px 60px rgba(0, 0, 0, 0.28);
  --shadow-focus: 0 0 0 4px rgba(255, 255, 255, 0.14);

  /* Motion */
  --duration-instant: 80ms;
  --duration-fast: 150ms;
  --duration-standard: 220ms;
  --ease-standard: cubic-bezier(0.2, 0.8, 0.2, 1);
  --transition-fast: var(--duration-fast) var(--ease-standard);

  /* Layers */
  --z-base: 0;
  --z-texture: -1;
  --z-sticky: 20;
  --z-overlay: 80;
  --z-skip-link: 100;
}