Drop down menu changes colors randomly

Hi again. The other issue I have with this theme (which didn’t fix when I re-installed) is that the colors in the drop down menu change randomly. They seems to default to (an unattractive) black background with white text (as if maybe it just isn’t registering any colors). However, sometimes it will change to a white background with the default a font color that matches the font of the parent menu items.

Ideally, I would also like to change the design of the drop down menus. Are either of these things I can fix/do with either of the Twenty-Twenty plug-in options? Right now I really don’t need them, but maybe I could use them for this. Thanks.

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