JSFiddle - React, Tailwind, and code Playground

by Zeaklous

HTML

<div class='pointer'></div>

CSS

.pointer {
    width: 0;
    height: 0;
    border-top: 5px solid transparent;
    border-left: 10px solid red;
    border-bottom: 5px solid transparent;
    position:relative;
}
.pointer:before {
    content:'';
    position:absolute;
    left:-15px;
    top:-10px;
    width: 0;
    height: 0;
    border-top: 10px solid transparent;
    border-left: 20px solid black;
    border-bottom: 10px solid transparent;
    z-index:-1;
}