Radio Button / Checkmarks not showing up in a form

So the radio buttons and the checkmarks have never been visible in my animal rescue website. And I’m trying to figure out why!

However, I know this is a theme issue. The forms work when I switch the theme to Twenty Twelve.

But what do I edit in my wordpress theme to correct this problem?

The website’s forms are here:
https://www.homelesspets.com/adoption-form/
https://www.homelesspets.com/fostering-form/

Thank you so very much!