You could try CSS like this:
.wp-show-posts-terms {
background-color: #000;
padding: 2px 7px;
}
.wp-show-posts-terms a {
color: #fff;
}
As for the forum rule, the second point specifically mentioned “Topics should be directly related to the theme or GP Premium. We’re not able to provide support for other plugins/services at this time. Basic coding help is allowed if it’s specific to theme/GP Premium features.”
https://www.screencast.com/t/id9EHS82