:root {
  /* ─── Border radius ───────────────────────────────────────── */
  --radius-xs: 2px;    /* legal / system-required surfaces */
  --radius-sm: 6px;    /* inputs, small inline buttons, grid cells */
  --radius-md: 10px;   /* content cards, article cards, cream callouts */
  --radius-lg: 12px;   /* primary CTA, signature surface cards, feature cards */
  --radius-pill: 9999px; /* pricing sub-system only */
  --radius-full: 9999px; /* circular icon buttons, avatars */
}