changing the home page content background to the colour black with white text

I have managed to change the content background to black and the text to white on the other pages, but cant do this on the home page. Also, i have a slider at the top that doesnt go all the way across on the homepage, how do I add a search box on the right hand side, next to the slider on the home page. All of this works fine on all other pages. many thanks.
url is http://www.diplomatportfolio.com