<x-radio> renders data-md-radio (data-md-inline), its legend, options,
rows and support as data-md-* attributes, and its layout moves into
components/radio.css: the 16px stack, the inline row from 600px, the
legend and the hint on the type and spacing tokens (plan step 36). A
label-less ring wears md-touch-target; the caller's style now lands on
the fieldset with its class.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9