JSFiddle - React, Tailwind, and code Playground

HTML

<div class='outerDiv'>
  <div class='innerDiv1'></div>
  <div class='innerDiv2'></div>
</div>

CSS

.outerDiv{
  width:300px;
  height:200px;
  margin:0px;
  padding:0px;
}
.innerDiv1{
  width:100px;
  height:200px;
  display:inline-block;
  background-color:red;
  margin:0px;
  padding:0px;
}
.innerDiv2{
  width:200px;
  height:200px;
  display:inline-block;
  background-color:green;
  margin:0px;
  padding:0px;
}