<!DOCTYPE html>
<html>
<head>
  <title>DOM tests</title>
  <meta charset="utf-8">
</head>
<body>
  <main>
    <section id="test-section">
      <div id="test1" class="item"></div>
      <div id="test2" class="item">
          <div id="child1"></div>
          <div id="child2"></div>
      </div>
      <div id="test3" class="item"></div>
    </section>
  </main>
</body>
</html>