JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
  <div class="col">
    <div class="block">
      123
    </div>
  </div>
</div>

CSS

.wrapper {
  position: fixed;
  top: 0;
  left: 0;
  width: 200px;
  height: 400px;  
  background-color: green;
}

.col {
  position: relative;
}

.block {
  position: absolute;
  top: 0;
  left: 0;
  width: 50px;
  height: 50px;
  background-color: gold;
}