Honestly I shouldn't be posting this at all, because it: a) has absolutely nothing to do with CSS/my code, and b) it's not my theme layer. Nevertheless, I get so many questions about this that I think I should just link to the tutorial I used and be done with it.
This tutorial will teach you (Paid users) how to make your metadata like this:

It's from a Flexisquares comm, but it works just fine with Smooth Sailing and Expressive, and probably most of the other styles as well.
CLICK HERE FOR THE TUTORIAL