If I look at the parsed html in Firefox/Firebug, as opposed to that in Chrome/Developer Tools, they are different.
Firefox has the div #contact within a font tag within a span within a paragraph. Chrome has the div as a direct child of #contacter. So, that's why it looks different in the two browsers.
So, fixing it....the validator is throwing an error related to your html - sixth one down: here
. It's quite possible that sorting that problem out that will resolve the issue. You have a div (a block element) within inline elements (font,span) and that's the error.
Really, I'd suggest removing all those <font> tags which are deprecated as well. Use css to apply your styling instead,
- we can view the code from the link provided - give Firebug
a go if you haven't tried it before.