Google Tag Manager Variable: Click classes incl. parent elements

var.js

/**
 * Click classes incl. parent elements 
 *
 * @return {string} containing all classnames of the click element and two parent elements
 * @description: Use the following code in a custom JavaScript macro variable in Google Tag Manager
 */

function() {
  classNames = "";
  el = {{Click Element}};
  
  for( var i = 0; i < 2; i++ ) {
    classNames += el.className + " ";
    el = el.parentElement;
  }

  return classNames;
}