title: How to create a self-closing HTML5 tag like <br>
body: <p>I want to basically make a custom tag that doesn't need to be closed and apply css to it.</p>
  
  <p>It shouldn't look like this:<code>&lt;customtag&gt;&lt;/customtag&gt;</code>.</p>
  
  <p>It should look like this: <code>&lt;customtag&gt;</code> or <code>&lt;customtag/&gt;</code>.</p>