html overlay for normal and dark mode?

hi,
I had created an HTML-overlay pop-up some months ago and it had kind of a dark mode theme. now I
just created a second version of my already existing pop up for the normal mode. my question is now, is it possible to have both in BTT so it would know whether I'm in dark mode or normal mode and change the pop-ups theme? or can I have both in and activate/deactivate one activate/deactivate the other one?

thanks