title: Why font size does not change?
body: <p>I want to set font size with <code>em</code>, not <code>px</code>. Here is my code:</p>
  <pre><code>&lt;style type=&quot;text/css&quot;&gt;
  body{
      font-size: 62.5%;
  }
  
  div{
      font-size: 1.2em;
  }
  &lt;/style&gt;
  
  &lt;body&gt;
  &lt;div&gt;hello world&lt;/div&gt;
  &lt;/body&gt;
  </code></pre>
  <p>I want to set <code>div</code> font size to be 12px, but it looks small than I expect, I disable <code>div</code> style with chrome browser tools, it does not look to have any change. What should I do to make <code>div</code> font size 12px?</p>