JSFiddle - React, Tailwind, and code Playground

HTML

<svg class="shadow" xmlns="http://www.w3.org/2000/svg" version="1.1">
    <defs>
        <filter id="f1">
            <feGaussianBlur in="SourceGraphic" stdDeviation="5" />
        </filter>
    </defs>
    <polygon points="200,0 200,200 0,200" filter="url(#f1)"/>
</svg>