JSFiddle - React, Tailwind, and code Playground

HTML

<html>
  <body>
    <div class="container">
      <div class="item">this is item</div>
    </div>
  </body>
</html>

CSS

.container{
  background-color:yellow;
  width:350px;
  height:200px;
  align-content:center;
  
}
.item{
  width:100px;
  background-color:gray;
}