Knocked layout out of kilter

I’m a novice, so all I can say was I was trying to figure out how to get the number listings to work on my webpage (as they worked in visual but not preview). I wasn’t saving only previewing all my changes, but suddenly the layout seems to have shifted out of kilter.

Can anyone tell me how to put it right again. The webpage is
http://www.wackynation.com/our-events/reverse-running

Thank you