how I can change Menu behaviour to open by click

Interesting - at first, I would have said it was not possible in css.
But with a bit of googling I found it can possibly done in css3.
Check out these links:
http://stackoverflow.com/questions/16912023/css3-transition-click-event
http://stackoverflow.com/questions/11166580/css3-transitions-is-there-an-on-click-option-without-using-jquery
http://jsfiddle.net/nMNJE/
and another one
http://vanseodesign.com/css/click-events/