function hideChildren(li) {
    for (var i = 0; i < li.childNodes.length; i++) {
        if (li.childNodes[i].nodeName == 'UL') {
            hideChildren(li.childNodes[i]);
            li.childNodes[i].style.display = 'none';
        }
    }
}

function openParent(node) {
    if(node.parentNode.parentNode.nodeName=='UL' && node.parentNode.parentNode.id !='nav'){
        node.parentNode.parentNode.style.display='block';
        node=document.getElementById(node.parentNode.parentNode.id);
        openParent(node);
    }
}

function toggleChildMenu(id){

    var activeMenu=document.getElementById(id);
    var activeMenuAsLink=true;
    for (var i = 0; i < activeMenu.childNodes.length; i++) {
            if (activeMenu.childNodes[i].nodeName == 'LI') {
               activeMenuAsLink=false;
            }
    }

    if(activeMenu.style.display == 'block'){
        activeMenu.style.display = 'none';
    }

    else if(activeMenu.style.display == 'none'){
        var nav=document.getElementById('nav');
        for (var i = 0; i < nav.childNodes.length; i++) {
            if (nav.childNodes[i].nodeName == 'LI') {
                hideChildren(nav.childNodes[i]);
            }
        }
        activeMenu.style.display = 'block';
        openParent(activeMenu);

    }

    return activeMenuAsLink;
    //return true;
}