How to interpret Appearance > Style colour coding?

[deanr72]

Is there some kind of key to interpretting the sequence of colours shown on the Appearance > Style menu?

As far as I can work out the right hand column (blue in my selected style shown in the screenshot) is the colour of the highlights throughout the desktop and running apps. Anything else?

The left hand side (grey) is the main colour of the windows but also has some seemingly undefinable / unrelated (?) effect on the whisker menu.

And what about the centre column? It doesn't seem to change the panel in any way. What changes am I not seeing?

And, while I'm here, how do these settings conflict with or compliment the Theme selector in MX Tweak?