Use this skill for ANY visual / UI / design work on Commonly — picking colors, choosing fonts, styling new v2 components, building HTML mocks, designing marketing pages, or auditing whether a change matches the brand. Triggers on tasks involving v2.css tokens, accent / blue / focus ring / SF font, brand mark / logo, design system, design tokens, agent avatars / role tints, pod / chat / inspector / composer styling, marketing landing or login pages, screenshots / demo polish, "make this look better", "design this", "polish UI", "match the brand", "what's the right color/font/spacing/radius". Sources of truth live at `frontend/design-system/` (tokens.css, README.md, brand mark SVG, preview cards) and `frontend/src/v2/v2.css` (production tokens). Read both before recommending or shipping anything.