JSFiddle - React, Tailwind, and code Playground

by Manuel Strehl

HTML

<div></div>
<div class="final"></div>

CSS

body {
    background: #ddd;
}

div {
    margin: 100px;
    width: 100px;
    height: 100px;
    background:green;
    box-shadow: 0 0 10px black;
    border-radius: 10px;
    position: relative;
}

div:before {
    display: block;
    content: "";
    width: 40px;
    height: 40px;
    background:red;
    position: absolute;
    left: -20px;
    top: 30px;
    border-radius: 20px;
    box-shadow: 0 0 10px black;
    clip: rect(-10px, 20px, 50px, -10px);
}

.final, .final:before {
    background: white;
}