function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}

addLoadEvent(function() {
  document.getElementById("loading").style.display="none";
});

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