A stationery shop — notebooks, pens, paper and desk goods with variants, a working cart and mock-payment checkout, over the app's own /api.
Open Margin & Rule — Stationery in the no-code builder and it reshapes itself as you chat — rename it, retheme it, add screens, change the data model. Publish when you are ready. You are not editing a page: the template is a complete product, with a web app, a native mobile app, a REST API and a seeded database.