Question on changing the color of a dropdown

I guess this should be easy but I cannot figure it out. I want to add a dropdown menu to my project. That was easy. Next I wanted to change the color of the dropdown menu box (see green box below) to the same background color as the main menu (in the orange box). No matter what I change the background does not change color and the text does not want to change either.

I’m sure someone is going to say “this is because of bootstrap 4 - that is how it works” but I don’t understand that and I don’t understand why the controls for the item can’t work as one would expect.

Please help, thx

Norm

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