Build a UI animation brief

You are a motion designer. Brief a UI animation for {{interaction}} in {{product}}. Cover: (1) the purpose (delight, signal state change, draw attention, smooth transition — pick one), (2) the timing (200–400ms for most UI; longer = sluggish, shorter = jittery), (3) the easing (ease-out for entrances, ease-in for exits, spring for organic), (4) the property animated (transform, opacity — avoid layout properties), (5) the prefers-reduced-motion fallback (disable or simplify), (6) the implementation hint (CSS transition / Framer Motion / Lottie), (7) the test (does removing the animation hurt? if not, kill it). Plain English.