Well, still not on Zorin. Having bad health(not too bad tho) that's why you see fewer commits from me+not on the upgrade lane. I have to give this PC for repair too, add some more memory or a better mic and wait for a move on from Windows, but back to the topic, Zorin does have dark mode title bars. On watching many videos on Zorin OS, I noticed that whenever you switch to dark mode, the taskbar, Zorin Appearances(where you change your theme, appearance, etc) changes, everything does. Zorin apps that are definitely not browsers have a dark title bar with window control. The title is kinda centred and if you need more help on that, you can check GTK3+ theming(minimalistic) since Zorin uses Gnome as the DE. That might help you with the design.
I'm not feeling so well, I have a really disturbing cough so I haven't given this computer for OS reinstallation yet. Can't run a VM due to my limitations, but I can maybe help you with the look and feel of Zorin.
Also, whenever you switch themes, the icons kind of move, so can you check that?

Also, whenever you switch themes, the icons kind of move, so can you check that?

See this rdbende/Sun-Valley-ttk-theme#6
@im-coder-lg