JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div class="back"> </div>
  <div class="box">boxeeeee boefw fewfwefw ef ewfw eff</div>
</div>



<div class="container">
  <div class="back"> </div>
  <div class="box">boxeeeee boefw fewfwefw ef ewfw ef f f f f f f f f f f f f f f f f f f f f f f f f f f f f f</div>
</div>

CSS

* {
  box-sizing: border-box;
}

.container {
  position: relative;
  margin: 100px;
  max-width: 100px;
  padding: 10px;
}

.box {
  border: 1px solid red;
  padding: 10px;
  max-width: 100px;
  min-height: 100px;
  background: gray;
  position: relative;
  z-index: 2;
}

.back {
  display: block;
  border: 2px solid red;
  border-radius: 12px;
  background: black;
  z-index: 1;
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  top: 0;
}