[ehnto]

They're still using HTML and CSS, all websites do. It's the dynamic and generated nature of web applications that makes static HTML and CSS not useful on it's own. You could argue the right choice then is a static site generator, but the difference between static site generation and dynamic site generation is really just when you do the generating work.

[tannhaeuser]

W3C, at least on their current site, have hardly any dynamic content beyond aggregated news/event snippets on the front page and maybe charter status pages and roadmaps published once every two years or so. Their collaboration workflow for spec text runs on github. They have gateways/integrations to external services (HTML validator) and a lot of static HTML.