JSFiddle - React, Tailwind, and code Playground

HTML

<div id="main">            
    <div id="NormalContent" class="content1">
        텍스트 1
    </div>
    <div id="FeaturedContent" class="content2">
        텍스트 2
    </div>
        <div class="content3">
        텍스트 3
    </div>
</div>

JavaScript

var content = document.getElementsByClassName('content3')[0];
var parent = content.parentNode;
parent.insertBefore(content, parent.childNodes[2]);