Variant Selector Preferences in Also Bought
In Also Bought it is possible to tune variant selector text, background, and border colours independently so that you can configure them to match the drop-down selector styles in your theme. You can find those preferences inside the 'Product variant' section, in the Visual preferences:
The variant selector text colour preference sets the text colour of the drop-down selector options.
The variant selector background colour sets the drop-down selector background colour.
While the variant selector border colour sets the drop-down selector border colour.