JSFiddle - React, Tailwind, and code Playground
HTML
<li class="menu">
<a class="mlink" href="#">link 1</a>
<div class="floatCK">
<div class="topCK"></div>
<div class="mainCK">
<ul>
<li><a href="#">another link</a></li>
<li><a href="#">another link</a></li>
<li><a href="#">another link</a></li>
<li><a href="#">another link</a></li>
</ul>
</div>
<div class="botCK"></div>
</div>
</li>
JavaScript
$("a.mlink").hover(function() {
$("div.mainCK").css({border: "1px solid red"});
},
function(){
$("div.mainCK").css({border: "none"});
});