Hi there,
i can’t see the Site stying. As a note we recommend only installing the Site libraries’ on a clean install not a website with content. In the case of where content is already added you can reset the GP settings in Appearance GP. You should also remove any Additional CSS that is added in the Customizer, and check if there are any Appearance > Elements > Headers or Hooks being used that you don’t need. As well as any pages / postss or menus the Library Site created.