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                <div id="output" class="box">

<div class="box" id="demo3a">
  <strong>Example 3a - User clicks a class</strong>
  <p class="instructions">
    Fire off the conversion pixel when visitor clicks the element of a particular class.

<!-- Copy this script tag -->
<script tag="text/javascript">
  // Example 3a - clicked element of ID
  window.onload = function()
  var example3 = {
  track_click: function() {
  _pq.push(["track", "User clicked"]);

  // Below is additional
  output.log("<hr>Example 3a fired!");
  var el = document.getElementById("demo3a"); = "#33CC66";
  var id = "demo3a";
  var el_3a = document.getElementById(id);
  el_3a.onclick = function() { example3.track_click(); }


                * {
  font-family: helvetica, arial;  

body {
  background-color: #e4e4e4;

.instructions {
  color: #444;

.box {
  background-color: white;
  padding: 20px;
  border: 1px solid #ccc;
  display: block;
  width: 50%;
  margin-top: 10px;
  border-radius: 4px;
  cursor: pointer;
  text-align: left;

.box:hover {
  background-color: #FFFF99;

#output {
  width: 40%;
  font-family: monospace;
  background-color: #fff;
  margin-left: 20px;


                (function() {
  window._pq = window._pq || [];
  var pa = document.createElement('script'); pa.type = 'text/javascript'; pa.async = true;
  pa.src = ('https:' == document.location.protocol ? 'https:' : 'http:') + "//";
  var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(pa, s);

var output = {
  log: function(txt) {
    var el = document.getElementById("output");
    el.innerHTML = el.innerHTML + txt + "<br>";