:root {
  /* neutrals (cool, quiet) */
  --paper: #f6f7f9;
  --paper-2: #f2f4f7;
  --paper-3: #eaecf0;
  --surface: #ffffff;
  --surface-2: #fafbfc;
  --line: #e4e7ec;
  --line-2: #d0d5dd;
  --line-soft: #f0f2f5;
  --ink: #101828;
  --ink-2: #475467;
  --ink-3: #667085;
  --ink-4: #98a2b3;

  /* action: quiet blue */
  --accent: #3d5fd6;
  --accent-2: #5674e0;
  --accent-ink: #2b47a8;
  --accent-soft: #f1f4fc;
  --accent-soft-2: #e1e7f8;

  /* AI: muted violet, reserved for AI surfaces */
  --ai: #7566c9;
  --ai-ink: #4f4497;
  --ai-soft: #f6f5fc;
  --ai-soft-2: #e8e5f6;

  /* states */
  --ok: #3b8f68;
  --ok-soft: #eef6f1;
  --warn: #b97a27;
  --warn-soft: #faf3e8;
  --bad: #c65a50;
  --bad-soft: #faefed;
  --stale: #a45a85;
  --stale-soft: #f8f0f4;
  --mute: #98a2b3;
  --mute-soft: #f2f4f7;
  --hl: #fbf3d9;
  --hl-2: #f5e6b3;

  /* classification */
  --cls-public: #3b8f68;
  --cls-internal: #475467;
  --cls-confidential: #b97a27;
  --cls-restricted: #c65a50;

  /* official document red (print layout only) */
  --gw-red: #c8161d;

  /* type */
  --font-ui: "Inter", -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Segoe UI", "Microsoft YaHei", sans-serif;
  --font-doc: var(--font-ui);
  --font-print: "Songti SC", "Noto Serif SC", "Source Han Serif SC", "STSong", "SimSun", serif;
  --font-fs: "STFangsong", "FangSong", "FangSong_GB2312", "Songti SC", serif;
  --font-mono: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;

  --fs-11: 11px;
  --fs-12: 12px;
  --fs-13: 13px;
  --fs-14: 14px;
  --fs-15: 15px;
  --fs-16: 16px;
  --fs-18: 18px;
  --fs-20: 20px;
  --fs-24: 24px;
  --fs-28: 28px;
  --fs-34: 34px;

  /* space (4px scale) */
  --s1: 4px;
  --s2: 8px;
  --s3: 12px;
  --s4: 16px;
  --s5: 20px;
  --s6: 24px;
  --s8: 32px;
  --s10: 40px;
  --s12: 48px;

  --r-xs: 5px;
  --r-sm: 8px;
  --r-md: 10px;
  --r-lg: 14px;
  --r-xl: 18px;
  --r-full: 999px;

  --sh-1: 0 1px 2px rgba(16, 24, 40, 0.05);
  --sh-2: 0 4px 12px -2px rgba(16, 24, 40, 0.08), 0 2px 4px -2px rgba(16, 24, 40, 0.04);
  --sh-3: 0 20px 40px -12px rgba(16, 24, 40, 0.18), 0 4px 8px -4px rgba(16, 24, 40, 0.06);
  --sh-page: 0 1px 3px rgba(16, 24, 40, 0.06), 0 12px 32px -16px rgba(16, 24, 40, 0.14);

  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
  --t-fast: 120ms;
  --t-med: 200ms;

  --topbar-h: 56px;
  --docbar-h: 58px;

  --z-sticky: 10;
  --z-pop: 50;
  --z-drawer: 60;
  --z-modal: 70;
  --z-toast: 80;
  --z-tip: 90;
}