Menu not showing

I’m loving this plugin, but somehow, while this site was still in stage, the menu just stopped working. I don’t think this is a css issue, I actually blanked the stylesheet out completely and tested the site and this still occurs.

When you tap the menu icon the overlay appears, but the menu itself does not.

I’ve been testing and wracking my brain for several days now. Any help is greatly appreciated!

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