JSFiddle - React, Tailwind, and code Playground

HTML

<div id="outer">
     <div id="inner1">
     </div>
     <div id="inner2">
     </div>
 </div>

CSS

#outer
 {
     position:absolute;     
     left:20%;
     right:20%;
     bottom:20%;
     top:20%;
     background-color:Blue;
  }

  #inner1
  {
      position:relative;
      width:20%;
      height:20%;
      background-color:Black; 
   }

   #inner2
   {
       position:relative;
       top:10%;   
       width:20%;
       height:20%;
       background-color:Red; 
   }