function showIt() {

if(document.getElementById("menu").style.zIndex<5) document.getElementById("menu").style.zIndex="8";
var allSelect=document.getElementsByTagName("SELECT");
for (i=0; i<allSelect.length; i++) {
 allSelect[i].style.visibility="hidden";
}

}

function hideIt() {

if(document.getElementById("menu").style.zIndex>5) document.getElementById("menu").style.zIndex="3";
var allSelect=document.getElementsByTagName("SELECT");
for (i=0; i<allSelect.length; i++) {
 allSelect[i].style.visibility="visible";
}

}