Some of the features on the Luna plan require small modifications to the Ghost theme. The easiest way to do this is to host your theme on our GitHub, which makes it possible to make changes to your theme and have them automatically update without going through the usual process of modifying a Ghost theme.
Generally, modifying a Ghost theme involves downloading a Zip file from your site, unpacking it on your local computer, editing the file locally, re-zipping the files, and uploading the zipped file again to check your changes. When your theme is hosted on our GitHub, you and your team have permissions to edit the files and can make changes quickly and easily.
Image Credit: NASA