JSFiddle - React, Tailwind, and code Playground

HTML

<div class="side-left block">контент<br>левой<br>колонки<br>самый<br>высокий<br>:)</div>
<div class="content block">основной конент</div>
<div class="side-right block">контент<br>правой<br>колонки</div>

CSS

.block { vertical-align: top; border: 1px solid #aaa; padding: 2px }

.side-left { display: inline-block; width: 20%; }

.content { display: inline-block; width: 50%; }

.side-right { display: inline-block; width: 20%; }

JavaScript

$( document ).ready(function() {
    
    var contentHeight = $('.content').height();
    var sideLeftHeight = $('.side-left').height();
    var sideRightHeight = $('.side-right').height();
    
    if (contentHeight < sideLeftHeight || sideLeftHeight < sideRightHeight) {
        $('.content').height(contentHeight + ((sideLeftHeight>sideRightHeight)?sideLeftHeight:sideRightHeight));   
    }
    
});