<h2 id="con">I love JavaScript</h2>

  <p> JavaScript使网页显示动态效果并实现与用户交互功能。</p>

  <script type='text/javascript'>

  var a = document.getElementById('con');

   a.style.color = 'red';

 a.style.backgroundColor = ''#CCC'';

// a.style.display = 'none';

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