Sorry, but there is no command base i know of, just do what i said earlier
here is a sample CSS code diplaying a bg pics
[css-div="-Moz-border-radius: 20px; -Webkit-border-radius: 20px; padding: 0px 0px 0px 0px; border; color: #000000; background-image: url('http://i224.photobucket.com/albums/dd251/hockeypanda32/Bg-3.png'); background-repeat: yes-repeat; background-position: 0px 34px; width: 930px;"]
here is a sample CSS code diplaying a bg pics
[css-div="-Moz-border-radius: 20px; -Webkit-border-radius: 20px; padding: 0px 0px 0px 0px; border; color: #000000; background-image: url('http://i224.photobucket.com/albums/dd251/hockeypanda32/Bg-3.png'); background-repeat: yes-repeat; background-position: 0px 34px; width: 930px;"]