概要
The Mobile-First Design skill provides Claude Code with a standardized framework for building modern, responsive web applications by prioritizing the small-screen experience. It enforces industry-standard breakpoints, touch-friendly UI patterns, and strict performance metrics to ensure websites are lightweight and accessible on low-bandwidth mobile connections before scaling up for desktop users. This skill is ideal for frontend developers who need to implement production-ready CSS architectures that emphasize relative units, accessibility, and progressive enhancement across all device types.
