/* Grounds and text roles — "Board & Paper".
 * Two grounds: paper (light) and night (blue-black, never neutral grey).
 * Ink is text on paper; chalk is text on night. Named by ROLE, not lightness. */
:root {
  --color-paper: #f7f6f3;
  --color-paper-raised: #fffefc;
  --color-paper-sunken: #f1efe9;

  --color-night: #0b0e18;
  --color-night-raised: #141928;
  --color-night-line: #232a3d;

  --color-ink: #16181d;
  --color-ink-muted: #5d6169;
  --color-ink-faint: #6b7079;
  --color-ink-slate: #4a4a4a;
  --color-rule: #e4e2db;
  --color-grid: #dedcd3;

  --color-chalk: #e8ebf4;
  --color-chalk-muted: #97a0b8;

  /* Semantic aliases */
  --surface-page: var(--color-paper);
  --surface-card: var(--color-paper-raised);
  --surface-well: var(--color-paper-sunken);
  --surface-dark: var(--color-night);
  --surface-dark-card: var(--color-night-raised);
  --text-body: var(--color-ink);
  --text-secondary: var(--color-ink-muted);
  --text-tertiary: var(--color-ink-faint);
  --text-on-dark: var(--color-chalk);
  --text-on-dark-secondary: var(--color-chalk-muted);
  --border-hairline: var(--color-rule);
  --border-hairline-dark: var(--color-night-line);
}