frontend

# Frontend

This file is a router, not a rulebook. The rules live in four rulesets under `references/`; your first job is to load the smallest set of files that covers the request, state which you loaded in one sentence, then execute under their guidance. Loading nothing and freestyling produces the generic AI-slop output this skill exists to prevent; loading everything wastes context and creates contradictory instructions.

**The bar is not clean-and-correct — it is work a senior designer at Linear, Stripe, or Supabase would ship.** Correct-but-flat is a failure, not a finish. Protect the surface as hard as you protect the build: design is a first-class deliverable, not a one-shot decision you lock and walk away from.

## Phase 0 — Route (before any UI work)

| Request involves… | Read |
|---|---|
| ANY UI implementation, styling, redesign, mockup, or visual decision | `references/design/README.md` FIRST. It enforces two mandatory gates — the Design System Gate (a `DESIGN.md` must exist before any component is written) and the React Dev Tooling Gate (react-grab / react-scan / react-doctor installed by default) — then routes to the taste and brand references below. |
| Interaction or motion work — micro-interactions, animated components, transitions, gestures, hover/press/state feedback, "make it feel alive" | ALSO `references/design/interaction-skill.md`. The beui.dev catalog is the mandatory interaction reference: find the nearest pattern, read its real source through the file's curl recipe, and adapt the mechanism to `DESIGN.md` motion tokens. It stacks on the routed style skill — never replaces it. |
| Writing or modifying frontend code, OR auditing performance / SEO / accessibility / quality | ALSO `references/perfection/README.md`. Lighthouse 100 in every category, measured on real Playwright Chromium (never the `lighthouse` CLI), achieved through architecture — never by dropping animations or hiding content. |
| Looking up a concrete style, color palette, font pairing, chart type, landing-page structure, or UX guideline — or generating a project design system from keywords | `references/ui-ux-db/README.md`. A searchable CSV database with a CLI; a lookup tool, not a posture. Load on demand; `design` stays the source of truth for taste and the `DESIGN.md` contract. |
| ANY implementation or redesign that creates or updates `DESIGN.md` — plus explicit operating-layer asks (personas, critique, debt, handoff, synthetic user testing) | `references/designpowers/README.md` + `references/designpowers/lane-c-review.md`. An internal frontend ruleset, not a separate skill: lane-c is the Phase Final flatness/critique reviewer, and its accessibility-constraints and accepted-debt language fills the required `DESIGN.md` sections. Load other lanes only when their phase applies. |

**For implementation work, design + perfection load together.** A page that hits Lighthouse 100 but looks like AI slop has failed; a page that looks beautiful but ships a 2 MB bundle has failed. Both win or neither does.

## Design System and Component Workflow

Every implementation must choose one of these branches before UI code changes:

1. **Concrete visual reference:** the user supplied a reference — treat it as the visual contract, then handle it by kind:
   - **Static visual reference** (screenshot, generated mockup, Stitch/Imagen output, Figma export, overview, or annotated packet): load `references/design/image-to-code-skill.md` plus the relevant design/perfection files, extract the reference's exact tokens, layout geometry, copy, spacing, states, and responsive intent into `DESIGN.md`, then implement reusable primitives against that contract.
   - **Live site or URL reference** (the user names a site to clone or gives a URL): load `references/design/clone-from-url.md`. Drive a real browser and extract the runtime truth via `getComputedStyle` — tokens, layout geometry, default/hover/focus/active states, transitions and keyframes, and downloaded assets — into `DESIGN.md`, then clone-code reusable primitives against that contract.
   Final QA for both runs `/visual-qa` in reference-fidelity mode: compare the actual UI against the reference pixel-by-pixel and verify the code is an extensible design-system implementation, not a screenshot-matched one-off.
2. **Greenfield or fresh setup:** if the user gave no concrete visual reference, design research is a build step with named deliverables — not exploration to be budgeted. Exploration-stop instincts ("enough exploration", two-wave caps) do not apply here. Fire every research lane IN PARALLEL before `DESIGN.md` is written, and open `DESIGN.md` with a `## 0. Research Log` section recording each lane's deliverable — a lane with no Research Log line did not run. Skip a lane only when its tool or network is genuinely unavailable, and name the skip in `DESIGN.md`:
   - **Embedded references:** use `references/design/_INDEX.md` to shortlist 2-3 plausible Layer B references, then read exactly one Layer A style skill and one Layer B reference in full — every line, no partial reads (they are 200-500 lines; a sliced read produces the flattened token set this gate exists to prevent). Log the shortlist, the pick, and why. Use `open-design` only when the curated set has no fit; add `ui-ux-db` lookups for palette/type/domain questions.
   - **Lazyweb real-product screens:** READ `references/design/lazyweb.md` FIRST and run its recipe verbatim — do not improvise curl calls against lazyweb.com; the recipe mints its own anonymous token. Log the queries run, how many screens you actually VIEWED, and the layout grammar harvested — never pixel copies.
   - **Imagen concept drafts:** generate 2-3 imagen concept drafts, each seeded with the loaded Layer A + Layer B tokens (palette, type, material); pick the strongest and treat the chosen draft as the reference-fidelity contract. Log the draft paths and the pick.
   Synthesize every lane into `DESIGN.md`. Treat sources as source material,