JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div>
    <div class="inner1"></div>
    <div class="inner2"></div>
  </div>
</div>

SCSS

.container {
  position: relative;
  width: 200px;
  height: 40px;
  background: green;
}

.inner1 {
  position: absolute;
  background: #444;
  width: 20px;
  height: 20px;
  right: -11px;
}

.inner2 {
  position: absolute;
  background: #444;
  width: 20px;
  height: 20px;
  left: 11px;
}