JSFiddle - React, Tailwind, and code Playground
HTML
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<ul class="list-categories">
<li class="cat-item cat-item-9"><a href="#" class="">All News (parent)</a>
<ul class="children">
<li class="cat-item cat-item-19"><a href="#" class="">Category 1</a>
</li>
<li class="cat-item cat-item-16"><a href="#" class="">Category 2</a>
</li>
<li class="cat-item cat-item-10"><a href="#" class="">Category 3</a>
</li>
</ul>
</li>
</ul>
CSS
.list-categories li {float:left; list-style:none;}
.list-categories li a {
background-color: #fff;
border-radius: 7px;
color:blue !important;
cursor: pointer;
display: block;
float: left;
font-size: 0.8em;
margin-left: 10px;
moz-border-radius: 5px;
padding: 0px 22px;
webkit-border-radius: 5px;
margin-bottom: 10px;
transition: 0.3s ease;
}
.list-categories li a.active-btn {
background-color:green;
color: #ffffff !important;
}
JavaScript
$(".list-categories li a").hover( function(){
$(this).toggleClass("active-btn");
});