I'm doing css for a website. I send the html and css to a guy, he puts it into ASP.net. The problem is that the transfer didn't end well for my code and it needs some fixing. The problem is that when I look at it in Chrome, or Firefox, or IE8, I get three completely different renderings. I spent a good amount of time trying to fix a drop-down menu that is supposed to appear while hovering over a link. The one he had in place from ASP.net worked in IE, kinda worked in Firefox, and was completely broken in Chrome (I haven't tested Safari or Opera.) Just getting it to look basically the same in firefox and chrome was a struggle. The html source is showing me two completely different pages as well.

Does anyone have experience with this? I know nothing of ASP.net, and it seems like the guy is modifying my layout with a wsyiwyg (I found tables used in random places, which I did not put there.) Faced with this, what is my best option? Is this fixable, or am I in over my head?