/* spec information about this property
name= background-image
css1= http://www.w3.org/TR/2008/REC-CSS1-20080411/#background-image
css2= http://www.w3.org/TR/2008/REC-CSS2-20080411/colors.html#propdef-background-image
css21= http://www.w3.org/TR/2011/REC-CSS2-20110607/colors.html#propdef-background-image
css3= http://www.w3.org/TR/2011/CR-css3-background-20110215/#the-background-image
*/