JSFiddle - React, Tailwind, and code Playground

HTML

<div id="centeredmenu">
<ul>
<li><a href='#'>Cat1</a></li>
<li><a href='#'>Cat2</a></li>
<li><a href='#'>Cat3</a>
<ul class='sub-menu'>
<li><a href="#">Sub Category</a></li>
<li><a href="">Sub Category</a></li>
</ul>
</li>
</ul>
</div>

CSS

#centeredmenu > ul li:nth-child(3){
    background:url(http://www.fabzin.com/Images/icon/arrow_down.png) no-repeat right top;
}