Using custom CSS, you can add a colored background to your posts without editing your posts in other ways and without changing the background of the rest of your blog's body.

Google says images styled with CSS won’t be indexed in Image Search, advising developers to use HTML tags for important visuals.

How to Add a Background Image to an OpenOffice Document. Adding an image to OpenOffice documents is a good way to brand printed material with a company logo or watermark, allowing your company's ...