#menu li {position: relative;}
#menu .sub_menu, #menu .sub_menu1 {display: none; position: absolute; margin-top: 0px; top: 0px; left: 235px; width: 235px; border-left: 1px solid #ccc; z-index: 2000;}
#menu .hover .sub_menu, #menu .sub_menu .hover .sub_menu1 {display: block;  }