JSFiddle - React, Tailwind, and code Playground

HTML

<div class="grid-container">
  <div class="grid-item">
      <div class="aspect-5-to-1"></div>
  </div>
  
  <div class="grid-item">
      <div class="aspect-1-to-2"></div>
  </div>
</div>

CSS

.grid-container {
  display: grid;
  grid-template-columns: repeat(2,50%);
}

.grid-item {
  border: 1px solid red;
  padding: 10px;
}

.aspect-5-to-1 {
  background: red;
  max-width:100%;
  padding-bottom: 20%;
}

.aspect-1-to-2 {
  background: blue;
  max-width:100%;
  padding-bottom: 200%;
}