JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/js/bootstrap.min.js"></script>
<div class="row">
    <div class="col-lg-4 col-md-4 col-sm-4 hidden-xs-down">
        Some content on the left that's going to be smaller than right
    </div>

    <div class="col-lg-8 col-md-8 col-sm-8 col-xs-12">
         A <br/>
         B <br/>
         C <br/>
         D <br/>
         E <br/>
         F <br/>
    </div>
</div>

CSS

.col-lg-4 {
  background-color: red;
}
.col-lg-8 {
  background-color: blue;
}