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                <div class="info">
  <p>This Pen is part of a series about ReactJS. <br>
    <a href="">Read the article</a> or 
    <a href="">see all ReactJS articles</a>.</p>

<div id="output"></div>


                $color--main: #E91E63;

* {
  margin: 0;
  padding: 0;
  box-sizing: inherit;

html, body {
  font: 20px/1.3 Arial, Helvetica, sans-serif;

.info {
  padding: 1rem;
  font-size: .75rem;
  border-left: .25rem solid $color--main;
  background: #f1f1f1;


                // Get the #output Element
var output = document.querySelector('#output');

// Create a new React Class (=Component) and assign
// it to the var HelloWorld. ReactJS/JSX Components MUST start with
// an uppercase, otherwise the interpreter will yell at you :)
var HelloWorld = React.createClass({
  render: function() {
    return <h1>Hello World!</h1>
// Next, we render the component into a DOM Element
React.render(<HelloWorld />, output);