Hints are no longer readable

At some point during the last couple days the hints have become unreadable on my quizzes. They appear as gray box and the text can’t be read. I have been using the same plugin and theme for a few years with no issues.

Here is the quiz page:

Fundamentals of Hot Stone Massage Quiz

I have also attached a screenshot. I use this plugin on another site with a different theme and it is doing the same thing, so that’s odd right?

Also, some of the quizzes have stopped showing results altogether. They start working again if I duplicate them and replace them, but it’s frustrating. I think something is going on.