title: font-awesome CSS in button
body: <p>I am having trouble deleting the outline of the button in CSS. I have to put the font awesome icon in button, so that it is accessible for screen . But I couldn't delete the outline of the button using outline:none or outline:0 in CSS. </p>
  
  <pre><code>  &lt;button class="fa fa-calculator" aria-label="calculator"&gt;&lt;/button&gt;
  </code></pre>