JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
			
			<div class="text-container">
				<p>blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah </p>
			</div>
      
 
      <div class="box-container">
      
			</div>
      
			
		</div>

CSS

*, *:before, *:after { -moz-box-sizing: border-box; -webkit-box-sizing: border-box; box-sizing: border-box; }

.container { border-radius:3px;box-shadow: 0px 4px 8px rgba(130, 130, 130, 0.25);position:relative; }

.text-container { overflow:hidden;padding:25px;width:70% }

.box-container { position:absolute;right:0;top:0;width:30%;height:100%;background-color:#F9F9F9;padding:20px}

JavaScript

var boxContainerH = $('.box-container').height();
$('.box-container').width(boxContainerH);