The fact of like is: browsers have a lot of differences, most of them don't follow the standards precisely, and I'm not sure that the Web standards precisely define the rendering of a page even if all the details are specified, nothing is left for defaults.
Therefore, there is no much sense in trying to achieve this goal. Your approach should be different. Please see some suggestions in my past answers:
crossBrowser and better designing[
^],
webpages layout change when running in different browsers.[
^],
Fix resolution and browser incompatibility[
^].
As to the note by Mehdi Gholam: basically he is right, frameworks (like jQuery) are created with browser compatibility in mind, so they can greatly improve things, but it is more relevant to the behavior, not subtle detail in layout, which are never 100% identical. And I also hope you are not trying to do ad-hoc formatting and use CSS consistently.
—SA