What problem does it solve? Building consistent, accessible interaction patterns for marketing and product websites requires re-implementing the same navigation, animation, and micro-interaction logic on every project, often with SSR pitfalls in Next.js App Router. ## Core Features & Use Cases - Navigation Patterns: Ready-to-use sticky header with scroll detection and mobile navigation using Sheet components with proper ARIA labels. - Motion Animations: Enter animations, staggered list animations, and scroll-triggered reveals using motion/react and Intersection Observer. - Micro-interactions & Accessibility: CSS hover states, button press effects, animated link underlines, and SSR-safe reduced-motion handling via useEffect. - Use Case: When building a landing page in Next.js, apply these patterns to add a sticky header that gains a backdrop blur on scroll, staggered card entrance animations, and hover lift effects on cards. ## Quick Start Ask the agent to implement a sticky header with scroll-triggered background and staggered entrance animations for the homepage cards using these UX interaction patterns.