JSFiddle - React, Tailwind, and code Playground

HTML

<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>
<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>

<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>
<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>
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<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>

<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>

<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>

<p>aaafsdffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff</p>

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<div>h</div>

CSS

div {
  background-color: #000;
  background-repeat: no-repeat;
  height: 500px;
  width: 500px;
  display: none;
    background-image: url("http://www.billboard.com/files/styles/promo_650/public/stylus/2029269-marilyn-manson-Agata-Alexander-617-409.jpg");
}

JavaScript

function isScrolledIntoView($elem) {
   var docViewTop = $(window).scrollTop();
   var docViewBottom = docViewTop + $(window).height();

   var elemTop = $elem.offset().top;
   var elemMiddle = elemTop + $elem.height()/2;
   return docViewBottom >= elemMiddle && docViewTop <= elemMiddle;
}
$(window).scroll(function(){
   $elem = $("div"); //or what element you like
   if(isScrolledIntoView($elem)){
      $elem.fadeIn(3000);
   }
});