:root{
  /* Rival leans on hierarchy, not boxes — radii stay small and are used sparingly.
     Photography is square-cut or full-bleed; pills are for actions and status only. */
  --radius-0:0px;        /* default: photography, data blocks, bands */
  --radius-4:4px;
  --radius-8:8px;        /* thumbnails */
  --radius-12:12px;      /* inputs, raised blocks */
  --radius-20:20px;
  --radius-full:999px;   /* buttons, status pills, form marks */
}