	<!-- //
	//getElementByClass function
	document.getElementsByClass = function (needle)
	{
	  var         my_array = document.getElementsByTagName("*");
	  var         retvalue = new Array();
	  var        i = 0;
	  var        j = 0;
	
	  for (i = 0, j= 0; i < my_array.length; i++)
	  {
		 var c = " " + my_array[i].className + " ";
		 if (c.indexOf(" " + needle + " ") != -1)
			retvalue[j++] = my_array[i];
	  }
	  return retvalue;
	}

	//This function must be called in a function which hides every element of a particular class:
	function hidebyClass(className) {
		var listeEle = document.getElementsByClass(className);
		for (i = 0; i < listeEle.length; i++) {
			var ele = listeEle[i];
			if (ele.style) ele = ele.style;
			ele.display = "none";
		}
	}
	
	// toggle visibility
	function toggle( targetId ){
	  if (document.getElementById){
			target = document.getElementById( targetId );
				if (target.style.display == "none"){
					target.style.display = "";
				} else {
					target.style.display = "none";
				}
		}
	}
	// -->