Hide an element with jQuery/javascript when the user is logged in

Hide an element with jQuery/javascript when the user is logged in

Hi All,

I would like to hide a menu item when the user is logged in already, here is my code but it doesn`t work properly:

I am checking if the user is logged in - (the top line works as it displays the alert message if I add one), but for some reason it doesn`t hide the menu item and the megamenu looks messed up when the user is logged in.
What would be the correct way to hide it?

Thank you
  1. function hideing() {
  2. if ($('#dnn_dnnUser_enhancedRegisterLink:contains("SuperUser Account")').length > 0) {
  3. document.getElementsByClassName['ul.megamenu li.level0:nth-child(4) .sub ul.megamenusubcontent:nth-of-type(1) li.subheader a'].style.visibility = hidden;
  4. }
  5. }