frontend-ui-animator

Analyze and implement purposeful UI animations for Next.js + Tailwind + React projects. Use when user asks to add animations, enhance UI motion, animate pages/components, or improve visual feedback. Triggers on "add animations", "animate UI", "motion design", "hover effects", "scroll animations", "page transitions", "micro-interactions".

$ インストール

git clone https://github.com/julianromli/ai-skills /tmp/ai-skills && cp -r /tmp/ai-skills/skills/frontend-ui-animator ~/.claude/skills/ai-skills

// tip: Run this command in your terminal to install the skill


name: frontend-ui-animator description: Analyze and implement purposeful UI animations for Next.js + Tailwind + React projects. Use when user asks to add animations, enhance UI motion, animate pages/components, or improve visual feedback. Triggers on "add animations", "animate UI", "motion design", "hover effects", "scroll animations", "page transitions", "micro-interactions".

Frontend UI Animator

Implement purposeful, performant animations that enhance UX without overwhelming users. Focus on key moments: hero intros, hover feedback, content reveals, and navigation transitions.

Core Philosophy

"You don't need animations everywhere" - Prioritize:

PriorityAreaPurpose
1Hero IntroFirst impression, brand personality
2Hover InteractionsFeedback, discoverability
3Content RevealGuide attention, reduce cognitive load
4Background EffectsAtmosphere, depth
5Navigation TransitionsSpatial awareness, continuity

Workflow

Execute phases sequentially. Complete each before proceeding.

Phase 1: Analyze

  1. Scan project structure - Identify all pages in app/ and components in components/
  2. Check existing setup - Review tailwind.config.ts for existing animations/keyframes
  3. Identify animation candidates - List components by priority category
  4. Document constraints - Note installed animation libraries (framer-motion, etc.)

Output: Animation audit table. See references/component-checklist.md.

Phase 2: Plan

  1. Map animations to components - Assign specific animation patterns
  2. Determine triggers - Load, scroll (intersection), hover, click
  3. Estimate effort - Low (CSS only), Medium (hooks needed), High (library required)
  4. Propose phased rollout - Quick wins first

Output: Implementation plan with component → animation mapping.

Phase 3: Implement

  1. Extend Tailwind config - Add keyframes and animation utilities
  2. Add reduced-motion support - Accessibility first
  3. Create reusable hooks - useScrollReveal, useMousePosition if needed
  4. Apply animations per component - Follow patterns in references/animation-patterns.md

Performance rules:

// ✅ DO: Use transforms and opacity only
transform: translateY(20px);
opacity: 0.5;
filter: blur(4px);

// ❌ DON'T: Animate layout properties
margin-top: 20px;
height: 100px;
width: 200px;

Phase 4: Verify

  1. Test in browser - Visual QA all animations
  2. Test reduced-motion - Verify prefers-reduced-motion works
  3. Check CLS - No layout shifts from animations
  4. Performance audit - No jank on scroll animations

Quick Reference

Animation Triggers

TriggerImplementation
Page loadCSS animation with animation-delay for stagger
Scroll into viewIntersectionObserver or react-intersection-observer
HoverTailwind hover: utilities or CSS :hover
Click/TapState-driven with useState

Common Patterns

Staggered children:

{items.map((item, i) => (
  <div 
    key={item.id}
    style={{ animationDelay: `${i * 100}ms` }}
    className="animate-fade-slide-in"
  />
))}

Scroll reveal hook:

const useScrollReveal = (threshold = 0.1) => {
  const ref = useRef<HTMLDivElement>(null);
  const [isVisible, setIsVisible] = useState(false);

  useEffect(() => {
    const observer = new IntersectionObserver(
      ([entry]) => entry.isIntersecting && setIsVisible(true),
      { threshold }
    );
    if (ref.current) observer.observe(ref.current);
    return () => observer.disconnect();
  }, [threshold]);

  return { ref, isVisible };
};

Usage:

const { ref, isVisible } = useScrollReveal();
<div ref={ref} className={isVisible ? 'animate-fade-in' : 'opacity-0'} />

Resources

  • Animation patterns: See references/animation-patterns.md
  • Audit template: See references/component-checklist.md
  • Tailwind presets: See references/tailwind-presets.md

Technical Stack

  • CSS animations: Default for simple effects
  • Tailwind utilities: For hover states and basic animations
  • Framer Motion: For complex orchestration, gestures, layout animations
  • GSAP: For timeline-based sequences (if already installed)

Accessibility (Required)

Always include in global CSS:

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}