JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div id="fader"></div>
    
    <div id="content">
        <h2>hoi</h2>            
    </div>
</body>

CSS

body {
 background:url("http://www.kingdomi.com/images/graphics/nature/nature6.jpg") top left no-repeat;   
}
#fader {
 background:rgba(255,255,255,0);   
 position:absolute;
 -webkit-animation:fader 3s;
    width:100%;
    height:100%;
    top:0px;
    left:0px;
}
#content {
 width:300px;
background:#fff;
border-radius:5px;
 margin:20px auto 0;   
    padding:30px;
}
@-webkit-keyframes fader {
    0% {background:rgba(255,255,255,1); }   
20% {background:rgba(255,255,255,0.8); }   
40% {background:rgba(255,255,255,0.6); }   
60% {background:rgba(255,255,255,0.4); }   
80% {background:rgba(255,255,255,0.2); }   
100% {background:rgba(255,255,255,0); }   
}