JSFiddle - React, Tailwind, and code Playground

HTML

<main>
  <div>
  
  </div>
</main>

CSS

body{
  margin:0;
  padding:0;
}
main{
    width: 100%;
    height: 100px;
    display: flex;
    flex-direction: column;
    background: red;
    justify-content: flex-end;
    align-items: center;
}
div{
  width:100px;
  height:50px;
  background-color:blue;
}