JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
  <span class="child">Centered text</span>
</div>

CSS

.parent {
  position: relative;
  height: 300px;
  background: #ddd;
}

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