JSFiddle - React, Tailwind, and code Playground

HTML

<nav>
			<ul>
				<li class="menu-pr"><a href="aceuille.php">aceuille</a>
					<ul class="sous-menu">
						<li><a href="#">#</a></li>
						<li><a href="#">#</a></li>
						<li><a href="#">#</a></li>
						<li><a href="#">#</a></li>
					</ul>
				</li>
				<li class="menu-pr"><a href="news.php">news</a>
					<ul class="sous-menu">
						<li><a href="#">#1</a></li>
						<li><a href="#">#1</a></li>
						<li><a href="#">#1</a></li>
						<li><a href="#">#1</a></li>
					</ul>
				</li>
				</ul>
			</nav>

CSS

body{
	font-family: 'Source code pro', Calbri, serif;
	margin: 0px;
	padding: 0px;
}

nav{
	width: 100%;
	background-color: #424558;
}

nav > ul{
	margin: 0px;
	padding: 0px;
}
nav > ul::after{
	content: "";
	display: block;
	clear: both;
}

nav > ul > li{
	float: left;
	position: relative;
}
nav > ul > li > a{
	padding: 20px 30px;
	color: #FFF;
}

nav li{
	list-style-type: none;
}

.sous-menu {
	display: none;
	opacity: 0.80;
}

nav a{
	display: inline-block;
	text-decoration: none;
}
nav li:hover .sous-menu {
	display: inline-block;
	position: absolute;
  width: 100%;
  background-color: green;
	top: 100%;
	left: 0px;
	padding: 0px;
	z-index: 1000;
}
.menu-pr:hover{
	border-top: 5px solid#e44d26;
	background-color: rgba(228, 77, 38, 0.15);
}

.sous-menu li:hover a {
	color: #EEE;
	font-weight: bold;
}
.submenu{
	display: none;
	color: black;
}
h1{
	width: 100%;
	height: 150px;
	background-color: #424558;
	color: white;
	font-size: large;
	line-height: 150px;
	text-align: center;
	font-family: cursive;
	border-radius: 3px;
	opacity: 0.80;
}
.entet{
	width: 100%;
	height: 150px;
	background-color: #424558;
	color: white;
	font-size: large;
	line-height: 150px;
	text-align: center;
	font-family: cursive;
	border-radius: 3px;
	opacity:0.80;
}