Refinement of the design "GUI"

Hello community. Guys, I’m using Seafile, but I want to make my own edits to the design of the project. How exactly can I implement this? There is a problem with the implementation of this task, as it just stops showing up - folders, files and the like from my data. Seahub himself does not see. Perhaps someone has already made their own adjustments solely for ease of use and will share their experience on how this can be implemented.