Give a color to the popup window @SELECT

I have noticed that the popup window has a new line - just under the title. A good choice to view what are you searching.
This was a parenthesis.
I just remembered that in an old TCC there was a possibility to change the color of background, foreground and selection bar when using @SELECT.
Now I cannot find how to do it.
Is it still possible ?
Thanks for help.
Florin