title: How to center pseudo element ::after border in a div?
body: <p>i want to ask you. I'm trying to create a border using pseudo element (after). I want to place a border in the middle of the div box that I have created, without setting (top, bottom) and (left, right). Can it be automated in the middle?</p>
  <p><a href="https://codepen.io/fikryrmdhna/pen/vYLqWJd" rel="nofollow noreferrer">My Codepen</a></p>
  <pre><code>&lt;div class=&quot;box&quot;&gt;
  &lt;/div&gt;
  </code></pre>
  <pre><code>.box{
    height:500px;
    width:300px;
    background-color:red;
    position:relative;
    
    &amp;::after{
      content:'';
      position:absolute;
      border:2px solid #fff;
      height:90%;
      width:90%;
    }
  }
  </code></pre>