What problem does it solve? Animation code often passes review because it technically works while feeling sluggish, firing too often, animating layout properties, or ignoring reduced-motion preferences. This Skill applies a strict, opinionated craft bar to motion code so feel-breaking regressions get flagged before they ship. ## Core Features & Use Cases - Standards-based review: Evaluates every animation against ten non-negotiable rules covering easing curves, sub-300ms durations, transform-origin correctness, GPU-only properties, interruptibility, and accessibility. - Structured findings output: Produces a Before/After/Why findings table plus a tiered verdict (feel-breaking regressions, performance, timing, accessibility) ending in an explicit Block or Approve decision. - Precise value citations: Pulls exact cubic-bezier curves, duration budgets, and spring configurations from a bundled standards reference instead of approximating. - Use Case: A developer opens a pull request adding a dropdown that animates with transition: all 400ms ease-in from scale(0). The review flags the unbounded transition, the ease-in curve, the over-budget duration, and the from-nothing scale, then prescribes transform 200ms with a strong ease-out from scale(0.95) plus opacity. ## Quick Start Ask the AI to review the animation and motion code in your current diff or pull request and report any violations with fixes.
