You'd think I'd remember that, given that it's my own advice, right? Advice, I might add, that I was paid to write, and am paid to teach.
If I had done that, I might have noticed that there was really very little contrast between those colors.
I should have listened to myself. Sigh.
(and yes, I will take these examples of What Not To Do to all of my classes. It'll be an excellent object lesson).