This codifies mobile-first responsive design practices into a skill that keeps your layouts consistent across breakpoints. It enforces the fundamentals: starting with mobile, using relative units instead of fixed pixels, maintaining 44x44px minimum touch targets, and structuring media queries properly. Useful when you're working with any component that needs to scale from phone to desktop, especially if you find yourself repeatedly explaining the same responsive patterns in code reviews. It won't teach you responsive design from scratch, but it will keep Claude from generating desktop-only layouts or using arbitrary breakpoints. Think of it as guardrails for the basics so you're not fixing viewport issues after the fact.
npx skills add https://github.com/am-will/codex-skills --skill frontend-responsive-design-standards