JSFiddle - React, Tailwind, and code Playground

HTML

<div class="pai">
  <div class="filho"></div>
</div>

CSS

.pai {
  width: 260px;
  height: 260px;
  background: red;
}

.filho {
  width: 80px;
  height: 80px;
  background: blue;
  float: right;
}