function showmenu(elmnt)
{
document.getElementById(elmnt).style.visibility="visible";
}
function hidemenu(elmnt)
{
document.getElementById(elmnt).style.visibility="hidden";
}
function toggleDiv()
{
    if (document.getElementById("myDivBox").style.display == "block")
    {
        document.getElementById("myDivBox").style.display = "none";
    } 
    else
    {
        document.getElementById("myDivBox").style.display = "block";
    }
}