A key as a tonic and a mode: twelve tonic buttons coloured like piano keys on a Base UI ToggleGroup (arrow keys, aria-pressed, never cleared by a second press, at least 24px square, the tonic filled with the value colour), and a Base UI Select of grouped modes named by its visible label and read with its value, portaled fullscreen-safe with the face's theme. Refused tonics are disabled with their reason; both values may be unset with a placeholder; renamable labels; one row of twelve or two of six.
pnpm dlx shadcn@latest add "https://pluginui.com/r/core-scale-picker.json"