JSFiddle - React, Tailwind, and code Playground

HTML

<div id="gallery">
  <img src="http://cl.vvmonnickendam.nl/files/large/87" alt="Awesome blabla gedoe">
</div>

CSS

html, body { height: 100%; }
    #gallery { height: 100%; width: 100%; position: relative; }
    
    #gallery img {
      /* CSS Hack will make it width 100% and height 100% */
      position: absolute;
      top: 0px;
      right: 0px;
      botoom: 0px;
      left: 0px;
      /* Maintain aspect ratio */
      max-height: 100%;
      max-width: 100%;
    }