/* Platform tokens — the only place colours, radii and type stacks are declared.
   Pages opt into a shelf by writing data-shelf on <html> (or on a band). */
:root {
  --bg: #FFF8F0;
  --surface: #FFFFFF;
  --ink: #191521;
  --muted: #6E6779;
  --line: #EDE4D8;
  --brand: #FF5C3D;
  --brand2: #FF9E3D;
  --violet: #6C4CFF;
  --mint: #12B886;
  --sun: #FFB020;
  --stage: #141020;
  --ad: #F4EEE4;
  --adline: #D9CDBC;
  --adink: #8A7F6E;
  --radius: 22px;
  --shadow: 0 12px 34px rgba(25, 21, 33, .09);
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, system-ui, sans-serif;
  --font-serif: Georgia, "Iowan Old Style", "Times New Roman", serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, "Roboto Mono", monospace;
  --fam-font: var(--font-sans);
}

/* Shelf: Mystery — dark, serif headings, amber accent. */
[data-shelf="story"] {
  --bg: #0c0b0f;
  --surface: #14121a;
  --line: #2d2739;
  --ink: #efe8dd;
  --muted: #9b9385;
  --brand: #e3b469;
  --brand2: #9a7f4e;
  --stage: #0a0910;
  --radius: 18px;
  --shadow: 0 18px 44px rgba(0, 0, 0, .55);
  --ad: #16131f;
  --adline: #332b45;
  --adink: #7f7590;
  --fam-font: var(--font-serif);
}

/* Shelf: Numbers — paper, grid lines, mono digits. */
[data-shelf="math"] {
  --bg: #f7f2e6;
  --surface: #fffdf7;
  --line: #e3ddd0;
  --ink: #14120f;
  --muted: #6b665d;
  --brand: #1b4dff;
  --brand2: #00a6a0;
  --stage: #efe9da;
  --radius: 6px;
  --shadow: 0 12px 30px rgba(20, 18, 15, .10);
  --fam-font: var(--font-mono);
}