Checkbox not acting like a checkbox (can't select)

I have a form consisting of nine single checkboxes. The idea is a user can select multi checkboxes under each heading and then submit the form.

However, my checkboxes do not "check" once they're clicked on. Not quite sure what the issue is. I tried to cut the code down and test it on JSFiddle, and the checkbox works fine there, but when previewing the page, it doesn't seem to work?

Checkbox working on JSFiddle.

Checkbox's not working on actual page.

Also, another minor issue, I can't seem to position the text in the grey background "Unsubscribe me from all types of emails" in line with the checkbox. I've tried adding margin-bottom:5px to the text, but it does't move?