Icons not loading

Hi. First off, I just installed and activated the plugin. I had some other things to do, and when I came back an hour later, I had already collected 2 email addresses without configuring anything – thanks for making that easy!

Unfortunately, it looks like the icons for the plugin aren’t loading for me. The ‘close’ button just shows a gray square, not like an X or anything. When I try to modify the design of the popup, I see a list of several icons, but they’re all the gray square. When I look at the social icons, they all look like gray squares as well. Was my installation off, or is something wrong with the plugin?

Thanks.

The page I need help with: [log in to see the link]