JSFiddle - React, Tailwind, and code Playground

HTML

<div class="darker"></div>

CSS

body {
  background: #eee;
}
.darker {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  padding-top: 50%;
  background: #dd4f39;
  overflow: hidden;
}
.darker::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: gray;
  transform: skewY(26.5deg);
  transform-origin: left top;
}