title: Github markdown - cannot change any style by inline-css and class
body: <p>I try to change font size and line height but failed. I've tried inline style:</p>
  
  <pre><code>&lt;div style="font-size: 12px; line-height: 12px;")&gt;bla&lt;/div&gt;
  </code></pre>
  
  <p>and class:</p>
  
  <pre><code>&lt;style&gt;
  .footnote {font-size: 12px !important; line-height: 12px !important;}
  &lt;/style&gt;
  
  &lt;div class="footnote"&gt;bla&lt;/div&gt;
  </code></pre>
  
  <p>and markdown syntax:</p>
  
  <pre><code>&lt;font size=1&gt;bla&lt;/font&gt;
  </code></pre>
  
  <p>None of them work. In Concole the DOM is just like:</p>
  
  <pre><code>&lt;div&gt;bla&lt;/div&gt;
  </code></pre>
  
  <p>and styles are always defined by default markdown: </p>
  
  <pre><code>.markdown-body {
      font-family: -apple-system,BlinkMacSystemFont,Segoe UI,Helvetica,Arial,sans-serif,Apple Color Emoji,Segoe UI Emoji;
      font-size: 16px;
      line-height: 1.5;
  }
  </code></pre>
  
  <p>Seems my setting takes no effect and even class is not added.<br><br>
  I also tried some other tags like <code>&lt;p&gt; &lt;span&gt;</code> but not working.<br><br>
  P.S. In VS Code Github Markdown preview it shows properly.</p>