The page loaded but the game did not start. This host is serving the repository source rather than a built site.
On GitHub Pages, that means the source is set to Deploy from a branch, which publishes these files through Jekyll — Jekyll cannot build this app, and it overwrites the real build on every push. Go to Settings → Pages → Source and choose GitHub Actions.
Choosing it is only half of the fix, and the half that catches people out: that
setting means “some workflow in this repository publishes the site”, and it
does nothing at all until one does. This repository ships
.github/workflows/pages.yml for exactly that. Check
Actions → Deploy to GitHub Pages — if it has never run, push a commit to the
default branch or run it by hand from that page.
Anywhere else, run npm install && npm run build and
serve the dist/ folder.