One corner scale, from small controls to large surfaces.
The base radius is 0.5rem. Buttons and inputs use rounded-lg, cards rounded-xl. A surface inside another takes the next step down, so corners stay concentric.
rounded-xs2pxrounded-sm4pxrounded-md6pxrounded-lgvar(--radius)rounded-xl12pxrounded-2xl16pxrounded-3xl20pxrounded-4xl24px