Sorry to interject, but that just seems wrong to my sensibilities.
html should be for content, not layout/style so resolution shouldn't matter.
Also, css shouldn't worry too much about screen size either. Really, the css classes should be tailored to be either fixed in size if you are really picky about the looks, else it should be left to resize dynamically with content...
If you want to position (or size) things that take screen sizes into account, you should do so dynamically with Javascript (anything else is a nightmare).
If the application is remotely complex and its all in one html file, it won't be readable so you don't need to bother with that.
btw, if you are serious about coding well structured readable javascript, look into this ressource:
http://jquery.com/