JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="nav">
	<li><a href="#">LINK1</a></li>
    <li><a href="#">LINK2</a>
    	<ul class="#">
        	<li><a href="#">LINK2a</a>
        		<ul class="#">
            	<li><a href="#">3 niovel</a></li>
        		</ul>
            </li>
    	</ul>
    </li>
    	<li><a href="#">LINK3</a></li>

</ul>

CSS

a, img { border:none; }
* { margin:0; padding:0; }
.nav{
	display:block;
	list-style:none;
	text-align: left;
    position: relative;
    height: 30px;
}
.nav li { 
	display: block;
	position: relative;
	float: left;	
	border: 1.5px solid #FFF;
}
.nav li a { 
	width: 125px;
	height: 30px;
	display: table-cell;
    vertical-align: middle;
	text-decoration: none;
	font-size: 12px;
	font-family: Arial, Verdana, Helvetica, sans-serif;
	text-align: center;
	color: #000;
	z-index: 2000;		
	background-color: #999;
}
li.active {
	background-color: #999 ;
	color: #000;
}
.nav li a:hover {
    top: 30px; 	
}

.nav li:hover > a {
	color:#fff;
	background-color:#333;	
}

.nav li > ul { 
	width: 125px;
	height: 25px;
	position: absolute;
	left: -9999px;	
	border: 1.5px solid #FFF;
}
.nav > li:hover > ul {
	left: -2px;
}

.nav li li:hover > a {
	color:#000;
	background-color:#999;	
}

.nav li li{ 
	position: relative;
	border: 1.5px solid #FFF;
	height: 25px;

}
.nav li li a {
	height: 25px;
	top: 25px;
	text-decoration: none;
	font-size: 9px;
	font-family: Arial, Verdana, Helvetica, sans-serif;
	text-align: center;
	display: table-cell;
    vertical-align: middle;
	color: #000;
	z-index: 2000;		
	background-color: #999;
}
li li.active {
	background-color: #a9d9d9 ;
	color: #007f7b;
}

.nav li > li:hover ul {
	left: -2px;
    top: 25px; 
}

ul.nav li > ul {
	width: 700px;
	height: 25px;
	background-color:blue;
}

ul.nav li > ul > li > ul {
	background-color:red;
	height: 45px; 
}


ul.nav li  ul ul { display: none; }
ul.nav li:hover > ul { display: block; }

ul.nav li ul ul {
    position: absolute;
    top:25px;
    left: -129px;
}

ul.nav li li:hover > a {
    color: white;
    background-color: #333
}