No, all of those areas are required to be defined within the WB skin. If you want to fundamentally run in Win10 dark mode, you may very well be interested in Curtains, it does exactly that - uses Win10 dark or light mode:
https://www.stardock.com/products/curtains/
You can have both WindowBlinds and Curtains installed at the same time, you don't need to pick one or the other. You can of course only have a theme from one of them applied at any one time.
