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                <h1>I help <span class="target-plural">startups</span> deliver more meaningful work. </h1>
    <form class="course-opt-in">
      <h4>Sign up for our free 5-day email course:</h4>
      <input type="email" />
      <input type="submit" value="Get lesson 1 today" />
<p> Change the string on line 32 of the JS file to change this page.</p>


                html, body {
  text-align: center; 
  font-family: helvetica, sans-serif;



                /* Converts a query string into an object. 
 * example input:  ?src=agency
 * results: { src: "agency" }
function parseQuery(str) {
  //Remove '?' from beginning.
  str = str.substring(1) 
  //split the string into key value pairs
  var pairs = str.split("&")
  //convert them into an object
  return pairs.reduce(function(map, pair) {
      var kv = pair.split("=")
      var key = kv[0]
      var value = kv[1]
      map[key] = value
      return map

//This function will change certain keywords on the page
function updatePlurals(text) {
  var targets = document.querySelectorAll(".target-plural"); 
  for(var i = 0; i < targets.length; i++) {
    targets[i].innerText = text;  

//How to get the data from the browser for real:
var query =
//Since this is a codepen, we'll have to mock it out. Change this string to change the page.
query = "?src=agency&subscriber=1"
var profile = parseQuery(query)

//Don't bug current subscribers with an email form. 
if(profile.subscriber) {
  document.querySelector(".course-opt-in").style.display = "none"

//Personalize the headline
switch(profile.src) {
  case "agency":
  case "freelancer":
   case "startup":