Create distinctive, production-grade frontend interfaces with exceptional design quality. Two modes - (1) New projects - bold aesthetic design philosophy including typography, color theory, spatial composition, motion design, visual details, avoiding generic AI aesthetics, creating unforgettable interfaces. (2) Existing codebases - mandatory design language analysis enforcing consistency by scanning layout patterns, typography hierarchy, component structure, spacing, theme systems before implementation. Use when building components, pages, applications, design systems, UI modifications. Covers React, Vue, Next.js, HTML/CSS, Tailwind. Keywords - create component, build page, design interface, add UI, aesthetic design, visual design, typography, animations, spatial layout, design system, consistency, pattern analysis, existing codebase.