JSFiddle - React, Tailwind, and code Playground

HTML

<div class="rectangle">&nbsp;</div>
<div class="circle">&nbsp;</div>

CSS

div
{
    position: absolute;
}

.circle
{
    top: -50px;
    width: 0px;
    height: 0px;
    border: 50px solid white;
    border-radius: 50px;
    background: transparent;
}

.rectangle
{
    height: 200px;
    width: 100px;
    background: #000;
}