Github bootstrap UI? Or github-like UI template

I really appreciate Github's website look & feel and I would like to "clone" it on a admin tool I'm developing right now.

Does anyone knows if there's a Github Bootstrakp (just like Twitter bootstrap) or something similar? Perhaps a Github-like UI admin template ...

I found their Style Guide page (https://github.com/styleguide/) but wasn't able to get the css and javascript source codes.