JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
  <div class="container">
    <div class="sub-container">
      <ul>
        <li><a href="#" data-color="red" class="red"></a></li>
        <li><a href="#" data-color="green" class="green"></a></li>
        <li><a href="#" data-color="blue" class="blue"></a></li>
      </ul>
    </div>
  </div>
  <div class="container">
    <div class="sub-container">
      <ul>
        <li><a href="#" data-color="red" class="red"></a></li>
        <li><a href="#" data-color="green" class="green"></a></li>
        <li><a href="#" data-color="blue" class="blue"></a></li>
      </ul>
    </div>
  </div>
  <div class="container">
    <div class="sub-container">
      <ul>
        <li><a href="#" data-color="red" class="red"></a></li>
        <li><a href="#" data-color="green" class="green"></a></li>
        <li><a href="#" data-color="blue" class="blue"></a></li>
      </ul>
    </div>
  </div>
</div>
<a href="#" class="animate-all">Animate All</a>

CSS

.wrapper{
  display: flex;
  flex-direction: row;
  padding: 20px;
  background-color: black;
}

.container {
  flex: 1;
  padding: 10px;
  transition: all 2s;
}

.sub-container {
  padding: 10px;
}

.sub-container ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  height: 300px;
  align-items: flex-end;
}

.sub-container ul li {
  flex: 1;
  margin: 10px;
  border: 3px solid #fff;
  padding: 10px;
  height: 60px;
}

.sub-container ul li a{
  display: block;
  width: 100%;
  height: 100%;
}

a.red {background-color: red}
a.green {background-color: green}
a.blue {background-color: blue}

JavaScript

/*
 * Each Color Rect is a link <a>.
 * You need to make these links clickable, 
 * each link should color its own container (parent element with class name ‘.container’) 
 * into the color from data-color attribute.
 * 
 * Link ".animate-all" should animate color switching of each container, from left to right  
 * with time interval of 2 seconds.
 */