We recently made the contents of our website (a Jekyll static site) public on GitHub: https://github.com/letsencrypt/website. Feel free to submit pull requests if you see errors or want to improve documentation.
Relatedly, the canonical location for documentation is now https://letsencrypt.org/docs/ instead of https://community.letsencrypt.org/c/docs. I’ll be updating the latter to replace them with links to the canonical location.