JSFiddle - React, Tailwind, and code Playground

HTML

<div id="outer">
    <div id="inner"></div>
</div>

CSS

div#outer {
    width: 100px;
    height: 100px;
    overflow: hidden;
    background-color: red;
    box-shadow: 10px 10px 10px 10px #000;
    border-radius: 10px;
}
div#inner {
    width: 100px;
    height: 100px;
    background-color: blue;
}