Controlling Specific Page Backgrounds and Navigation Elements

Hi!

I hope I can explain this without babbling too much.

I want to have a different background image, or color for certain pages that are powered by wordpress. For example, I may want the “about” page to have a blue background and the “Call Me” page to have a gray one.

How would I do this in wordpress? I know the CSS, and whatever – but how would I call this in the template? I do stuff like this in Movable Type all the time, but since the templates are static, and the content is dynamic, I just add something like a ID to the body tag, and have that control different pages backgrounds.

I have the same question about doing so with navigation elements, like is done in the “Blix” theme. I believe that’s all controlled by PHP though – for example, when a visitor on the “home” page I want, say, the background of that navigation element to be yellow, instead of the default color of black.

Thanks for any help!