/* spec information about this property
name= visibility
css1= NA
css2= http://www.w3.org/TR/2008/REC-CSS2-20080411/visufx.html#propdef-visibility
css21= http://www.w3.org/TR/2011/REC-CSS2-20110607/visufx.html#propdef-visibility
css3= http://www.w3.org/TR/2007/WD-css3-box-20070809/#visibility
*/