JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div id="submain">
        <div class="backgr">a</div>
        <div class="backgr">b</div>
        <div class="backgr">c</div>
        <div class="backgr">d</div>
        <div class="backgr">e</div>
        <div class="backgr">f</div>
    </div>
</body>

CSS

.backgr{background:#f00;}

JavaScript

$(document).ready(function(){
  function chbck(){
    $("div.backgr:last").animate({opacity:0}, 3000, function(){
      $("div.backgr:last").prependTo("div#submain");
      $("div.backgr:first").css("opacity","1");
      setTimeout(chbck,6000);
    });
  }
  setTimeout(chbck,6000);
});