JSFiddle - React, Tailwind, and code Playground

HTML

<div class="okno">
</div>

CSS

.okno {
   width:200px;
   height:100px;
   background:url('http://lorempixel.com/200/200/') no-repeat;
   -webkit-transition: height 1s;
   transition: height 1s;
 }
.okno:hover{
   height:200px;
}