css3 - CSS: Opaque overlay with transparent div sections -

i'm developing system site want page turn opaque when activated except divs can receive on.

the problem can't figure out how specific divs "appear" transparent on top of opaque background.

i tried setting z-index of divs value higher background doesnt seem work.

here jsbin illustrating issue. "help" class should appear transparent (i.e. not opaque)

http://jsbin.com/ifohuc/1/edit

thanks.

you must set position attribute of li.help in css file

for example

position:relative;