JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
  <div class="left">

  </div>
  <div clas="right">

  </div>
</div>

CSS

.parent{
    width:100%;
    heigth: 100%;
    min-height:100%;
    overflow:hidden;
}
.left{
    float:left;
    width:60%;
    height: 100%;
    overflow:hidden;
    background-color: Red;
    }
.right{
    width:40%;
    height: 100%;    
    overflow:hidden;
    background-color: Blue;    
}