The webpage uses Jekyll. The template for the index is at _layouts/index.html.

If you want to add a new translation, follow these steps:

1. Copy index_fr.html to index_{langcode}.html and update its lang and permalink values.
2. Copy _data/locales/en.yml to _data/locales/{langcode}.yml and update its initial language code.
3. Change the values of the English strings to the new, translated language strings.

You can see the translated webpage by running bundle install and bundler exec jekyll serve, after executing it open http://localhost:4000/ and switch to your language.