JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
  <textarea id="my-text-area"></textarea>
</div>

CSS

body,
html,
#container {
  width: 100px;
  height: 100px;
}

body {
  margin: 0px;
}

#container {
  position: relative;
}

#my-text-area {
  position: absolute;
  top: 0px;
  bottom: 0px;
  left: 0px;
  right: 0px;
  width: inherit;
  height: inherit;
}