UI Animation

• IS: designing, implementing, reviewing, debugging UI motion (springs, gestures, drag, easing, CSS transitions, keyframes, framer-motion), and measuring motion from a recording (extract frames, track, fit curves) to emit code plus a handoff spec.
• IS NOT: choosing overall visual direction, palettes, or typography (use ui-design), auditing a whole page's UI quality (use ui-audit), or named text-effect specs (use the external animate-text skill where installed).

Canonical home for reverse-engineering motion from a recording: route "reverse engineer this animation" and "match this easing" here, not to a separate skill. If the input is a screen recording or video, you are MEASURING motion: follow the Reverse-engineer workflow. Otherwise (designing, implementing, reviewing) use the rules and Workflow below.

Reference files