Source of the project website — plain hand-written HTML/CSS/JS, no build step, served by nginx.

Not in this folder (added at deploy time):

• img/ — built by build-images.sh <dist>/img: the five screenshots from ../assets/screenshots/ as PNG plus WebP at 480/600/1170 px (served through <picture>), banner.png, and social.jpg (1200×630, the og:image on every page)
• icon-180.png / icon-512.png — copied from ../frontend/public/ (the same icons the PWA uses, so the browser tab, home screen and app all match)
• openGym.apk — the signed release build (see ../docs/MOBILE.md)
• demo/ — the browser-only demo build of the app, embedded in the #demo section and reachable on its own at /demo/. Built from ../frontend with VITE_DEMO=1 and the jsDelivr media bases (see the pages job in ../.gitlab-ci.yml), so the ~140 MB of exercise media stays out of it. It has to live on this host: the site frames it, and X-Frame-Options: SAMEORIGIN would block it from anywhere else.

Navigation is a topic rail (.side): one title/subtitle list of everything on the site, a fixed column beside the page from 1300 px up and the hamburger sheet below that, with a scrollspy lighting the section under the reader. The top bar keeps only the brand, GitHub, Discord and the download button.

site.js carries five independent pieces, each one failing soft so the page is complete without any of them: the topic-rail sheet, its scrollspy, the scroll reveals, the demo iframe (injected only once the frame is on screen, and never below 700 px, where the CSS swaps it for an "open it full-screen" card), and the two things that come from the public api.github.com at view time — the star/issue counts and the About page's release timeline. Both wait for requestIdleCallback so they never compete with the hero image.

Every page starts with a "Skip to content" link (.skip, visible on focus) that targets <main id="main">. Screenshots change under the same file name, and nginx caches images for seven days — bump the name if a new one must show up at once.

api.html is the one generated file in here: node scripts/build-api-docs.mjs rewrites it from ../api/openapi.yaml. Edit the spec, re-run the script, commit both — never hand-edit api.html, the next run overwrites it. The page is static HTML in this site's own design (no Swagger UI, nothing rendered at view time); the only script of its own it carries is the contents drawer and the card expand/collapse.

styles.css and site.js are cache-busted with ?v=N — nginx serves the site with no-cache, must-revalidate, but the query bump is what saves a Cloudflare edge from handing out an old stylesheet with new markup. Bump it on every change.