描述
Senior frontend engineering expertise for building high-quality web interfaces. Use this skill when writing, reviewing, or optimizing frontend code - HTML, CSS, JavaScript, TypeScript, components, layouts, forms, or interactive UI. Triggers on web performance optimization (Core Web Vitals, bundle size, lazy loading), accessibility audits (WCAG, ARIA, keyboard navigation, screen readers), code quality reviews, component architecture decisions, testing strategy, and modern CSS patterns. Covers the full frontend spectrum from semantic markup to production performance.