/* ==========================================================================
   Anthropic Design System — Design Tokens
   "Research journal printed on warm stone"
   ========================================================================== */

:root {
  /* ---- Colors ---- */
  --color-slate-dark: #141413;
  --color-ivory-light: #faf9f5;
  --color-ivory-medium: #f0eee6;
  --color-ivory-dark: #e8e6dc;
  --color-oat: #e3dacc;
  --color-cloud-medium: #b0aea5;
  --color-cloud-light: #d1cfc5;
  --color-cloud-dark: #87867f;
  --color-slate-medium: #3d3d3a;
  --color-slate-light: #5e5d59;
  --color-clay: #d97757;
  --color-accent-ember: #c6613f;
  --color-olive: #788c5d;
  --color-sky: #6a9bcc;
  --color-fig: #c46686;
  --color-cactus: #bcd1ca;

  /* ---- Surfaces ---- */
  --surface-page-base: #faf9f5;
  --surface-nav-elevated-light: #f0eee6;
  --surface-oat-card: #e3dacc;
  --surface-feature-dark: #141413;

  /* ---- Typography: Font Families ----
     Anthropic Sans substitute → Quicksand (warm rounded grotesque)
     Anthropic Serif          → Anthropic Serif (provided)
     Anthropic Mono substitute → ui-monospace stack
     Chinese display          → Smiley Sans (subsets loaded) */
  --font-sans: 'Quicksand', 'Anthropic Sans', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: 'Anthropic Serif', ui-serif, Georgia, Cambria, "Times New Roman", Times, serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --font-zh: 'Songti SC', 'Source Han Serif SC', 'Noto Serif SC', 'STSong', 'PingFang SC', serif;

  /* ---- Typography: Scale ---- */
  --text-caption: 12px;
  --leading-caption: 1.3;
  --text-body-sm: 15px;
  --leading-body-sm: 1.4;
  --tracking-body-sm: -0.03px;
  --text-subheading: 18px;
  --leading-subheading: 1.4;
  --text-heading-sm: 20px;
  --leading-heading-sm: 1.4;
  --text-heading: 24px;
  --leading-heading: 1.3;
  --tracking-heading: -0.12px;
  --text-heading-lg: 61px;
  --leading-heading-lg: 1.1;
  --tracking-heading-lg: -1.22px;
  --text-display: 91px;
  --leading-display: 1.1;

  /* ---- Typography: Weights ---- */
  --fw-regular: 400;
  --fw-medium: 500;
  --fw-semibold: 600;
  --fw-bold: 700;

  /* ---- Spacing (base unit 4px) ---- */
  --spacing-4: 4px;
  --spacing-8: 8px;
  --spacing-12: 12px;
  --spacing-16: 16px;
  --spacing-24: 24px;
  --spacing-32: 32px;
  --spacing-48: 48px;
  --spacing-76: 76px;
  --spacing-84: 84px;

  /* ---- Layout ---- */
  --page-max-width: 1200px;
  --content-width: 1000px;
  --section-gap: 76px;
  --card-padding: 31px;
  --element-gap: 16px;

  /* ---- Border Radius ---- */
  --radius-lg: 8px;
  --radius-2xl: 16px;
  --radius-3xl: 24px;
  --radius-cards: 8px;
  --radius-panels: 16px;
  --radius-featuredcards: 24px;
  --radius-buttons: 0px;

  /* ---- Motion ---- */
  --ease: cubic-bezier(0.2, 0.6, 0.2, 1);
  --dur: 220ms;
}