JSFiddle - React, Tailwind, and code Playground

HTML

<div id="no_background"></div>
<div id="wrapper">
  <input type="button" id="test" value="Show background">  
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</div>

CSS

body {
    background: #000;
}

#no_background {
  background: white;    
  position: fixed;
  left: 0px;
  top: 0px;
    width: 100%;
    height: 100%;
  z-index: 1;
}

#wrapper {
    position: relative;
  z-index: 2;
}

JavaScript

$("#test").click(function() {
  $("#no_background").fadeOut();
});