JSFiddle - React, Tailwind, and code Playground

HTML

<body>
<div class="centrar">
    <IMG id="im1" SRC="http://www.simplefoto.com/wp-content/uploads/et_temp/2011-08-17-1440-27-JCT-copy-90822_128x128.jpg">
    <IMG id="im2" SRC="http://www.simplefoto.com/wp-content/uploads/et_temp/2011-08-17-1440-27-JCT-copy-90822_128x128.jpg">
    <IMG id="im3" SRC="http://www.simplefoto.com/wp-content/uploads/et_temp/2011-08-17-1440-27-JCT-copy-90822_128x128.jpg">
</div>
</body>

CSS

.centrar {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}