This is a Jeyll-based website for the Global Security Database documentation. It is currently in a very initial-state and is based on the default minima theme. The minima GitHub page has detail on how to customize the theme.
The .bundle/config is configured to install Gems in the local directory rather than on your system.
You should be able to build and test this site on your own system using the following commands:
bundle install
bundle exec jekyll serve
This will start a local webserver for you to browse and test you changes.