Highlight for Dark Background

My theme has a black background, and white text, I want to make a full purchase, but it’ll be a waste because, the orange highlighting doesn’t show up when a comment is made, and when you click on the commented text, the highlighting shows up and the comments made, but, the the orange background doesnt go well with the white text, it’s too bright, i’d love to make a full purchase, but I cannot use it like that.

https://wordpress.org/plugins/hypercomments/