JSFiddle - React, Tailwind, and code Playground

HTML

<div id="nav" style="position: absolute; width: 430px; height: 50px; z-index: 10; left: 35px; top: 10px;">
    
    
    <ul id="menu">
    <li class="nodrop" style="z-index: 7;"><a href="#">Home</a></li>
    <li style="z-index: 5"><a href="#">Topic</a>
    <ul>
    <li style="z-index: 4"><a href="#">Subtopic 1</a></li>
    <li style="z-index: 4"><a href="#">Subtopic 2</a></li>
    <li style="z-index: 4"><a href="#">Subtopic 3</a></li>
    </ul></li>
    <li class="nodrop" style="z-index: 1;"><a href="#">Page 2</a></li>
    </ul>
    
    </div>

CSS

}

#menu {
    list-style-type: none;
    margin-bottom: 10px;
    position: relative;
    clip: rect(auto, auto, auto, auto);
    margin-top: 0px;
    height: 50px;
    width: 430px;
    margin-left: 50px;
}
#menu li {
    float: left;
    position: relative;
    }
    
#menu a {
    text-decoration: none;
    color: #000000;
    display: block;
    padding: 15px 15px 15px 15px;
    margin: 0 20px 0 20px;
    position: inherit;
    font-family: Helvetica, verdana, arial, sans-serif;
    font-size: 17px;
    font-weight: bold;
    text-shadow: 1px 0px 0px black;
    text-shadow: -1px 0px 0px black;
    text-shadow: 0px 1px 0px black;
    
}
#menu ul {
    position: absolute;
    list-style-type: none;
    left: -9999px;
    background-color: #FFFFFF;
    
}
#menu ul li {
    float: none;
    
}
#menu ul a {
    white-space: nowrap;
}
#menu li:hover ul {
    left: 0px;
}
#menu li:hover a {
    color: #003577;
    padding: 5px 10px 10px 10px;
    margin: 10px 25px 0 25px;
    border-radius: 15px 15px 0px 0px;
    -moz-border-radius: 15px 15px 0 0;
    -webkit-border-radius: 15px 15px 0 0;
    font-size: 17px;
    text-shadow: none;
    background-color: #F4C829;
    border-top-style: solid;
    border-top-color: #000000;
    border-right-color: #000000;
    border-left-color: #000000;
    border-top-width: 2px;
    border-right-width: 2px;
    border-left-width: 2px;
    border-left-style: solid;
    border-right-style: solid;
    position:relative;
    z-index:5;
}
#menu li:hover li:first-child a{
    border-top:2px black solid;
}
#menu li:hover li:last-child a{
    border-bottom:2px black solid;
}
#menu li:hover ul{
    position:relative;
    top:-2px;
}
#menu li.nodrop:hover a {
    margin: 12px 23px 10px 23px;
    background-color: #000000;
    color: #FFFFFF;
    padding: 3px 12px 5px 12px;
    border-radius: 15px 15px 15px 15px;
    -moz-border-radius: 15px 15px 15px 15px;
    -webkit-border-radius: 15px 15px 15px 15px;
    font-size: 17px;
    text-shadow:...