Design and build bespoke, self-contained HTML pages at artifact grade — design docs, product design briefs (PDs), proposals, reports with UI mockups. Use AUTOMATICALLY whenever a page's visual quality is part of the deliverable ("make it polished", "design doc as a page", "like a Claude artifact"), whenever authoring a design/proposal page in a product repo, and whenever a document needs a product-surface mockup, flow strip, or phase cards. Produces the HTML; publish-page or a product repo hosts it.
