JSFiddle - React, Tailwind, and code Playground

HTML

<div class="A">
  <div class="B">
    I WISH I WAS AS BIG AS MY DAD
  </div>
</div>

CSS

.A {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  background: #00b;
  -ms-flex-direction: column;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
  flex-direction: column;
}

.B {
  background: #b00;
  -ms-flex-grow: 1;
  -webkit-box-flex: 1;
  flex-grow: 1;
}