One line that tunes a component: useTune(name, (t) => ({ … })) returns typed live values and builds a litt Inspector for them. Every corner, space and spring is checked against litt's rules as you drag, values sit on litt's tokens once they fit, takes are saved as versions, and Copy tokens writes litt's own names. The panels show only in development unless you turn them on.
pnpm dlx shadcn@latest add "https://littmd.vercel.app/r/tune.json"