One geometry in src/iso/mark.ts, drawn by the engine the miniatures use. The favicon follows the system's mode; scripts/favicon.mjs takes its colors from styles.css. Below 768px the header shows the mark alone, its word kept as the link's name.
The build fetches showcase.lock's commit and runs the catalog's own validator. /showcase/ lists featured apps first, then the rest by newest or stars, with categories and search; /showcase/<id>/ shows previews, links and the README. The header drops its sound switch below 414px so the fourth link fits.