JSFiddle - React, Tailwind, and code Playground

HTML

<div class="navbar navbar-fixed-top">
        <div class="navbar-inner">
        <ul class="nav">
            <li><a href="#">Home</a></li>
        </ul>
        </div>
    </div>

CSS

.navbar{
    border-radius:50% 50% 0 0;
    background:#000;
    min-height:100px;
}