function showLeftNav(){
 hiddenLeftMenu = true;
 document.getElementById('leftnavcontent_open').style.display = "block";
 document.getElementById('leftnavcontent').style.display = "none";
 document.getElementById('leftnavcontentshow').style.display = "block";
 document.getElementById('leftnavcontentshow').className = "pullDown";
}

function hideLeftNav(){
 document.getElementById('leftnavcontent_open').style.display = "none";
 document.getElementById('leftnavcontent').style.display = "block";
 document.getElementById('leftnavcontentshow').style.display = "none";
 document.getElementById('leftnavcontentshow').className = "";
 hiddenLeftMenu = false;
}