Screen resolution - read from a cookie

I am building a site in WordPress. I need to be able to detect the screen resolution and change templates used accordingly. I have written some code (php and javascript) that is doing exactly this. In some instances it is appending a parameter to the URL ( eg /?width=*clientresolution* ). the problem with this is that the page is reloading to accept the parameter and so when you click back on the browser you simply cycle back to the same page. The manual way around this is to double click, but of course that is ok. I need a solution that will remember the screen res during a session (or beyond) either through cookie or some other means - and so still affect the change in the IF statement that I have built (OR I need another way of doing it!). Typically visitors will come via the home page, but this may not always be the case and so allowance needs to be made for this. The site could be viewed on a desktop (Mac or PC) or a Mobile phone - hence the need to change the look of the page. The look is substantially different that an alternative css won't work. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Win Mac Mobile IE 6+ FF 2+ No additional plugins No client downloads HTML, Javascript, PHP all acceptable.