JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" class="menu" onMouseOver="a_hover();" onMouseOut="a_out();">hover me</a>

<div id="here">it's work :)</div>

CSS

#here {display:none;}

JavaScript

$(document).ready(function(){
$('.menu').hover(function(){
    $('#here').fadeIn("slow");}).mouseout(function(){
        $('#here').fadeOut("slow");});
});