jQuery addClass example

Change class name on click in jQuery

HTML

<div id="myForm">
  <div id="section_0">
    CLONE DIV!
  </div>
  <button type="button" id="addDiv" class="btn btn-primary">add</add>
  </div>
<script>
globalSectionId = 0;
$("#addDiv").click(function (){
console.log('ea')
     $("#myForm div#section_0").clone().attr({id:`section_${++globalSectionId}`}).appendTo("#myForm"); 
    // clone(). and set the new id with the .attr() - Thx @Phil
 });</script>

CSS

body {
  background: #20262E;
  padding: 20px;
  color:white;
}

#banner-message {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  font-size: 25px;
  text-align: center;
  transition: all 0.2s;
  margin: 0 auto;
  width: 300px;
}

button {
  background: #0084ff;
  border: none;
  border-radius: 5px;
  padding: 8px 14px;
  font-size: 15px;
  color: #fff;
}

#banner-message.alt {
  background: #0084ff;
  color: #fff;
  margin-top: 40px;
  width: 200px;
}

#banner-message.alt button {
  background: #fff;
  color: #000;
}