I am trying impress.js out but I wonder i there is a way to change the background color of the body for some slides. I would like my first 3 slides to have a different background then the rest.
Unlike reveal.js perhaps,it is not possible,
You can use jimpress http://jmpressjs.github.com/jmpress.js/#/home
here is a demo in which background changes
http://tympanus.net/Tutorials/SlideshowJmpress/
customize it as per your requirements so as to remove the slide structure