Single Page Background Colour

Hi there! I was wondering if there was a way to have a different colour background for a single page? I don't want it as bright a blue as it is on the rest of my site. My website is www.blue-jay.co.uk and the page ID is 499 (http://blue-jay.co.uk/gallery-2/) I've tried:

body.page-id-499 {
    background-color: #222930;
}

Both in Custom CSS and in the body section of the Style Sheet to no effect? (p.s. these were tried separately, not at the same time lol) Any help would be great!