JSFiddle - React, Tailwind, and code Playground

HTML

<div id="dimScreen"></div>

CSS

#dimScreen {
    width: 100%;
    height: 100%;
    background:rgba(0,0,0,0.5); 
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100; /* Just to keep it at the very top */
}