Create a temporary standalone validation page on a spike branch when architecture or feature behavior needs isolated visual verification.
Use this skill when the user asks to add a standalone validation page, demo route, smoke test page, or an isolated visual verification surface.
spike/tailwind-v4-lab or spike/router-layout-check./ reserved for the product-facing homepage or dashboard.src/spikes/<topic>/./__spike/tailwind-v4 or /__spike/router-layout.pnpm test:unit -- --run.pnpm build when routes, styles, or utility classes change.