JSFiddle - React, Tailwind, and code Playground

HTML

<div class="flex-container">
  <div id="item1">
  
  </div>
  <div id="item2">
  
  </div>
</div>

CSS

.flex-container{
  height:300px;
  width:300px;
  display:flex;
  align-items:center;
  justify-content:center;
  background-color: #ffeeee
}

#item1{
  width:100px;
  height:100px;
  background-color:blue;
}

#item2{
  width:120px;
  height:120px;
  background-color:red;
}