Theme Studio Questions

If these questions are covered in documentation somewhere, please point me in the right direction. (I'm still on 10.1).

In 10.2/10.3 Theme Studio:

  1. Is it possible for the site banner to inherit its scope/functionality in sub-groups but still be themed differently?
  2. Can a theme include a different banner logo image for each theme?
  3. If it's not possible for a sub-group site banner to inherit from the root and be themed differently, is it possible to specify a specific group (site root) in the Site Navigation option for "Include Group Navigation" without modifying the Site-Banner widget code?

Example: Site root has light theme with banner logo image that has black text with transparency to white/grey (scrolled) background but a sub-group is dark themed so the site banner should switch to dark theme including banner logo image to one with white text and transparency to dark background. The site navigation "hamburger" menu should show the same content for both groups (site root group list with avatars and descriptions).

I'm mocking some of this up in 10.1 using CSS overrides, but the site-banner widget keeps stomping on my custom styles when I inherit and if I don't inherit, I only get the sub-group's groups in the navigation "hamburger" menu (but it looks visually correct). (Also I don't trust replacing an image on a page using CSS)