title: Border of qgroupbox
body: <p>I'm having some trouble setting a border of a groupbox.</p>
  
  <p>my aim is to have something like this:</p>
  
  <p><img src="https://i.stack.imgur.com/0Z1wc.png" alt="enter image description here"></p>
  
  <p>but so far all I can get is this:</p>
  
  <p><img src="https://i.stack.imgur.com/KT2iJ.png" alt="enter image description here"></p>
  
  <p>the stylesheet i'm using:</p>
  
  
  
  <pre><code>#groupBox {
      border: 1px solid gray;
      border-radius: 9px;
  }
  </code></pre>