Transitions Polish

Transitions Polish

An add-on to the transitions-dev skill. Where transitions-dev installs whole transitions, this skill polishes motion that already exists: it scans the five motion-token dimensions — duration, distance, scale, blur, easing — and suggests the token each value should reference, plus the higher-order rules for when a value is right (open/close asymmetry, hover in/out, stagger, delay).

Install it alongside transitions-dev, or on its own — the token values are restated below so this skill can audit a project standalone. When it is installed, the transitions.dev Refine panel automatically feeds these rules into every Small refinement job.

Core doctrine: match on usage, never on the nearest number

A value is not "wrong" because it is off by 20ms. It is wrong when it does not fit what the motion does. Always infer the usage first — modal close, dropdown open, tooltip, badge appear, page slide, text reveal, shake — then pick the token whose documented usage matches. A 300ms modal close maps to --duration-quick (150ms) because both are "modal close", even though the numbers differ. If a value's usage matches no token usage, leave it untouched. Never force a swap just because a number is close.

The five dimensions

Same scale the transitions.dev Motion tokens tab exposes. Copy this skill's _root.css into your project once; once imported, reference any token as var(--…). The transitions-dev transitions ship literal values, so they work without these tokens — install this skill to tune them against the shared scale.

Durations

Easings

--ease-smooth-out is the default. Nudge generic ease, ease-in, or any hand-rolled cubic-bezier(...) / linear(...) toward it only for surface motion (open/close, slide, resize, position). Leave the other five token easings alone — they are already on-grid and each carries its own intent.

Distances

Travel distance scales down with frequency and up with ceremony: an in-place text swap barely moves (4px), a page slide travels a readable 8px, a one-off celebratory badge can sweep 30px. If a translate distance is larger than ~40px for anything but a full panel/drawer, it usually reads as sluggish — pull it toward --distance-base.

Scales

The captured value is the non-resting "pre" scale the surface animates from; it always settles to 1. Bigger surfaces start from further away (0.96 modal), small hints barely scale (0.98–0.99). A pre-scale below ~0.9 reads as a "zoom" and rarely fits UI chrome — snap it to the usage token.

Blur

Blur is the non-resting "pre" blur, settling to 0. Use it to soften a swap or slide, never on a plain fade or a color/theme change. Blur can be absent as well as off-token: when the usage clearly calls for one (a page slide with no blur lane) suggest adding --blur-medium.

Polish rules — when a value is right

Open/close asymmetry

Opening is an invitation; closing should get out of the way. Closes are faster and quieter than opens.

• Duration: dropdown/modal open 250ms → close 150ms (--duration-fast → --duration-quick); panel open 400ms → close 350ms (--duration-slow → --duration-medium); toast close 350ms (--duration-medium).
• Symmetric exceptions — same duration + easing both ways, do NOT split: page side-by-side (250ms), tabs sliding (250ms), accordion (250ms), icon swap (250ms), text swap (150ms). These read as a single reversible motion, not an open/close pair.
• Distance & blur: the enter phase carries the distance and blur; the exit can drop or shrink them so a close doesn't fling content across the screen.
• Easing: most opens and closes share --ease-smooth-out. Overshoot curves belong to entrances only (badge pop, number pop-in) — never bounce a close.

Hover in vs hover out

• In: quick and direct — a short --duration-fast-or-less lift with --ease-smooth-out.
• Out: softer and springier — the return can take longer and use --ease-bounce-strong (avatar return, cubic-bezier(0.34, 3.85, 0.64, 1)) so the row settles instead of snapping. This is the one place the out is more elaborate than the in.

Stagger and delay

• Stagger offset: --duration-stagger (40ms) per item; step up to --duration-micro (80ms) for a few large items. Keep the total stagger (offset × item count) under ~300ms so the last item doesn't feel late — for long lists, cap the number of staggered items or shrink the offset.
• Intent delay: a tooltip waits --duration-micro (80ms) before appearing so a passing cursor doesn't trigger it; the success-check path draw uses the same 80ms beat. A delay is right when you want to filter accidental triggers or sequence two things — not to pad a slow animation.
• Delay vs duration: if motion feels late, prefer trimming the duration over adding delay. Reserve delay for stagger, intent gating, and deliberate sequencing.
• Never delay a close or a hover-out — dismissal must feel instant.

Commands

The skill exposes two namespaced verbs. Every command starts with transitions so the invocation never collides with verbs from other skills installed in the same project. review reports; polish applies.

transitions review — audit motion against the tokens

Trigger phrases: transitions review, "review my animations", "audit the motion", "scan for ad-hoc transitions", "tokenize my animations", "where are my durations off", "align to the motion tokens", "make the timing consistent".

Behaviour:

1. Scan the whole project — not just stylesheets, but inline style= / CSS-in-JS, styled-components, <style> blocks, and Tailwind arbitrary values (duration-[300ms], [transition-timing-function:...]) — for all five dimensions: durations (…ms/…s), easings (cubic-bezier(...) / keywords), translate distances (translate*(…px)), scale(...), and blur(...). Read @keyframes via the animation that drives them.
2. For each value, infer what the motion does from the surrounding selectors / component names (modal close, dropdown open, tooltip, badge appear, page slide, text reveal, shake, hover lift, …). Look the usage up in the token tables above and pick the token whose documented usage matches — usage first, never nearest number. Do not suggest whole-transition recipe swaps; that is transitions-dev's transitions apply domain.
3. Apply the polish rules: check open/close asymmetry, hover in/out, stagger totals, and delays — not just whether a single value is on-grid.
4. Output a numbered list grouped by file, showing only values that should change:
   • path/to/Component.css:L42 — modal close: 300ms → var(--duration-quick) (150ms) — close should be quicker than the 250ms open.
   • path/to/List.css:L20 — stagger: 120ms → var(--duration-stagger) (40ms) — 8 items × 120ms = 960ms total, last item feels late.
   • Skip values whose usage matches no token — list them as no matching token usage and leave them.
5. Do not edit anything. End with: "Run transitions polish to apply these changes, or confirm any line to apply individually."

transitions polish — apply motion-token refinements

Trigger phrases: transitions polish, "polish my transitions", "refine the motion", "tune the timing / easing", "apply the motion tokens", "fix the stagger", "tokenize my animations".

Behaviour:

1. If the user has not run transitions review in this session, run the same scan from transitions review first (steps 1–4) to build the change list. If they named a specific file, line, or value, scope the scan to that context.
2. Surface a short proposal: how many values would change, grouped by file, with one example line. Ask for confirmation before editing.
3. On confirmation, apply the token changes to the source:
   • Replace hardcoded durations/easings/distances/scales/blur with var(--…) references where the project's _root.css (this skill's _root.css) is already imported; otherwise write the token's literal value and note that importing _root.css would let future tweaks happen in one place.
   • Keep the file's existing unit/format (0.25s vs 250ms) unless switching to var(--…).
   • Touch only the motion values being polished — no reformatting, no unrelated edits.
   • Handle plain CSS, CSS Modules, styled-components/emotion, Tailwind utilities/config, inline style objects, and Motion/Framer variants.
4. If _root.css is not yet in the project, offer to install it (once) before or alongside the polish pass.
5. Keep the diff small. End with a one-line summary of files touched.

Relationship to the Refine panel

When this skill is installed in a project, the transitions.dev Refine panel's Small refinement tab automatically inlines the compact rules in _refine-rules.md into its agent prompt, so per-click suggestions honor these rules with zero extra file reads. transitions review mirrors that audit at project scale; transitions polish writes the accepted tweaks to source.

Future expansion

Natural next additions to this skill: performance hygiene (transition: all, animating width/top/box-shadow instead of transform/opacity, will-change misuse), missing prefers-reduced-motion detection, a cross-project consistency audit (same-purpose transitions using different values), Tailwind/Framer token adapters, and a "motion polish score" report.