Add a doctype. To quote VIPStephan
HTML 4.01 looks to be the closest to what you have. Add that, and then validate you mark-up (Link to validator: http://validator.w3.org/) and see if that helps. It should show you where your unclosed divs are if nothing else.
Without such browsers switch to quirks mode (because you don’t tell them what kind of language you are using) and each browser is guessing what you could have meant (and they guess differently).
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
@021414: There's a link to the page ;-)