JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
<div class="one">I am one I am one I am one I am one</div>
<div class="two">I am two I am two</div>
</div>

CSS

.container {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
}

.one, .two {
  background: green;
  color: white;
  flex-grow: 1;
  margin-bottom: 1rem;
}

.one {
  flex-basis: 77%;
  margin-right: 5%;
}

.two {
  flex-basis: 18%;
}