JSFiddle - React, Tailwind, and code Playground

HTML

<nav id="main-nav" class="main-nav">
    <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">Dropdown &darr; </a>
            <ul id="sublist">
                <li><a href="#">Tomorrow</a></li>
                <li><a href="#">Doomoro</a></li>
            </ul>
        </li>
        <li><a href="#">Contact</a></li>
        <li><a href="#">About</a></li>
    </ul>
</nav>

CSS

nav{position:relative;}
nav ul{max-width:480px;margin:40px auto}
nav li{list-style:none; float:left;position:relative}
nav ul li a {
font-family:'Cookie', cursive;
background-color:#400000 ;
border-radius: 0.5em;
color:#fff;
display:block;
line-height:3em;
text-align:center;
text-decoration:none;
padding:6px 12px;
}

nav ul li a:hover {
    background-color:#680000 ;
    color:white;
}

nav ul ul {
    display: none;
    position: absolute;
    top: 20px;
    left:0;
    padding:0
}

nav ul li:hover ul {
  display: block;
  position: absolute;
  opacity: 1;

}
nav ul li:hover li {
    float: none;
}

#sublist li a {
    font-family:'Cookie', cursive;
    background-color:#400000 ;

    border-radius: 0.3em;
    color:#fff;
    display:block;
    line-height:3em;
    text-align:center;
    text-decoration:none;
    width:100%;
}