JSFiddle - React, Tailwind, and code Playground

HTML

<div class="grid">
  <div class="box1">red</div>
  <div class="box2">green</div>
</div>

<div class="grid">
  <div class="box1">red</div>
  <div class="box2 absolute">green</div>
</div>

CSS

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin-bottom: 20px;
}


.box1 {
  background: red;
  height: 80px;
}

.box2 {
  background: green;
  height: 80px;
}

.absolute {
  position: absolute;
}