JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bemvindo">

</div>

CSS

.bemvindo{
  border: 1px solid grey;
  width: 100px;
  height: 100px;
}

.animated{
  background: #333;
}

.bounceInDown{
  border-color: red;
}

JavaScript

$(function(){
  $(".progresso").delay(5000).fadeOut();
  $(".preloader").delay(5000).fadeOut("slow");
  $('.bemvindo').addClass('animated bounceInDown');
});