:root {
  /* ─── Color: Surfaces ─── */
  --color-bg-page: #f7f7f8;
  --color-bg-surface: #ffffff;
  --color-bg-surface-hover: #fafafa;
  --color-bg-surface-active: #f5f5f5;
  --color-bg-elevated: #ffffff;
  --color-bg-inset: #f0f0f2;
  --color-bg-sidebar: #0a0a0b;
  --color-bg-sidebar-hover: rgba(255, 255, 255, 0.06);
  --color-bg-sidebar-active: rgba(255, 255, 255, 0.1);

  /* ─── Color: Text ─── */
  --color-text-primary: #0a0a0b;
  --color-text-secondary: #64646b;
  --color-text-tertiary: #9d9da5;
  --color-text-inverse: #f4f4f5;
  --color-text-sidebar: rgba(255, 255, 255, 0.55);
  --color-text-sidebar-active: #ffffff;

  /* ─── Color: Border ─── */
  --color-border: #e8e8ec;
  --color-border-light: #f0f0f2;
  --color-border-heavy: #d4d4d9;
  --color-border-focus: #0a0a0b;
  --color-border-sidebar: rgba(255, 255, 255, 0.08);

  /* ─── Color: Accent ─── */
  --color-accent: #0a0a0b;
  --color-accent-hover: #1a1a1d;
  --color-accent-text: #ffffff;

  /* ─── Color: Status ─── */
  --color-success: #00a63e;
  --color-success-bg: #edfcf2;
  --color-success-border: #b6f0cc;
  --color-danger: #dc2626;
  --color-danger-bg: #fef2f2;
  --color-danger-border: #fecaca;
  --color-danger-hover: #b91c1c;
  --color-warning: #d97706;
  --color-warning-bg: #fffbeb;
  --color-warning-border: #fde68a;

  /* ─── Spacing ─── */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;

  /* ─── Radii ─── */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 10px;
  --radius-xl: 12px;
  --radius-2xl: 16px;
  --radius-full: 9999px;

  /* ─── Typography ─── */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'SF Mono', 'Cascadia Code', 'Fira Code', 'JetBrains Mono', monospace;

  --text-xs: 11px;
  --text-sm: 13px;
  --text-base: 14px;
  --text-md: 15px;
  --text-lg: 16px;
  --text-xl: 18px;
  --text-2xl: 22px;
  --text-3xl: 28px;

  --leading-tight: 1.2;
  --leading-normal: 1.5;
  --leading-relaxed: 1.65;

  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;

  --tracking-tight: -0.02em;
  --tracking-normal: -0.011em;

  /* ─── Shadows ─── */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06), 0 1px 3px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08), 0 2px 6px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.1), 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-ring: 0 0 0 3px rgba(10, 10, 11, 0.08);
  --shadow-ring-focus: 0 0 0 3px rgba(10, 10, 11, 0.16);

  /* ─── Transitions ─── */
  --transition-fast: 120ms ease;
  --transition-base: 180ms ease;
  --transition-slow: 280ms ease;

  /* ─── Layout ─── */
  --sidebar-width: 260px;
  --header-height: 56px;
  --content-max-width: 1200px;
}