title: How to display a modal inside a parent container
body: <p>I have a small sub-window like <code>div</code> in my app, and I need to display a modal inside the sub-window instead of the whole viewport.</p>
  
  <p>So the backdrop of the modal should only cover the sub-window and not the entire screen</p>
  
  <p>I am using material-ui, so any solution native to material-ui is preferred.</p>