JSFiddle - React, Tailwind, and code Playground

by David Thomas

HTML

<div class="demo">Some arbitrary, purely-demonstrative and otherwise irrelevant, content to fill out the div element.</div>

CSS

.demo {
    height: 20vh;
    position: relative;
}
.demo::after {
    content:'';
    display: block;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    height: 1em;
    background-color: #000;
    -webkit-clip-path: polygon(0 0, 45% 0, 50% 50%, 55% 0, 100% 0, 100% 30%, 55% 30%, 50% 80%, 45% 30%, 0% 30%)
}