I need to change style on a page depending on if it's a handheld device (such as a cell phone) or a large screen device, such as a laptop, stationary pc or a tablet. I know I could detect the reso...

I have designed my site with a 900 x 600 fixed background image. On the computer it looks fine. How will it look on a PDA device? Will I have to design it separately for PDA? How should check whet...