$(document).ready(function() {
       $(".menuPoint").mouseover(function(){
          var id = $(this).attr("class").split(' ');
	      $("#menu_"+id[1]).css("z-index","100");
        
	   }).mouseout(function(){
	      var id = $(this).attr("class").split(' ');
          $("#menu_"+id[1]).css("z-index",id[1]);
	   });
});