JSFiddle - React, Tailwind, and code Playground

HTML

<div class="header">
  <div class="left">

  </div>
  <div class="center">
  
  </div>
  <div class="right">
  
  </div>  
</div>

CSS

.header {
  display: flex;
  flex-direction: row;
  height: 50px;
}

.left {
  width: 25%;
  background-color: red;
  height: 100%;
}

.center {
  width: 50%;
  background-color: green;
  height: 100%;
}

.right {
  width: 25%;
  background-color: blue;
  height: 100%;
}