function showdiv(menu,x,y) {
                        hidediv();
                        document.getElementById(menu).style.left = x+'px';
                        document.getElementById(menu).style.top = y+'px';
                        document.getElementById(menu).style.visibility = 'visible';
            //            document.getElementById("ocultar").style.visibility = 'visible';
            }

            function hidediv() {
                        document.getElementById("menu1").style.visibility = 'hidden';
                        document.getElementById("menu2").style.visibility = 'hidden';
                        document.getElementById("menu3").style.visibility = 'hidden';
                        document.getElementById("menu4").style.visibility = 'hidden';
              //          document.getElementById("ocultar").style.visibility = 'hidden';
            }

	    function toggle_visibility(id) {
		 var e = document.getElementById(id);
	         if(e.style.display == 'block')
                    e.style.display = 'none';
                  else
                    e.style.display = 'block';
	    }