Adding color coded tabbed browsing to TopNav?

[Korkus]

Is there any way in which I could incorporate a tab style coloured menu within TopNav? In the attached image you can see an example of what I'm trying to achieve.
https://imgur.com/a/FfN94V1

My project has five major areas and the ideal situation would be to color code each topic so no matter where you are in the project you know which section you are in.
Ideally, I'd also like to be able to extend this color coding to the left TOC but again, I'm not sure this is possible without some major coding which I want to avoid.

Any help would be much appreciated.

[rogersm]

Perhaps the following might be a start for you: https://www.smartoutput.com/persistent- ... re-topnav/