Extra white space on Zerif Lite pages, between tickets to purchase

I have Zerif Lite installed, with My Calendar and My Tickets. There is a lot of white space between the tickets. You can see it here (https://creative-oasis.com/mc-events/bracelet-making-bistro-dinner-included/?mc_id=3). I emailed the question to the author of My Tickets, and he said…

“I tried to figure out what was causing those large spaces – but I can’t see it. I can’t see any evidence in the CSS of any reason that large space between types of tickets would be there. It certainly shouldn’t that should take up considerably less space on the page.

I did a test install of your theme, and I can tell you for certain that the extra space is coming from the theme in some way, but I couldn’t see what was causing it.”

Anybody here have ideas?