JSFiddle - React, Tailwind, and code Playground

HTML

<button></button>
<button></button>
<button></button>

CSS

button {
  width: 30vmin;
  height:30vmin;
  border: 1vmin solid #888;
  box-sizing: border-box;
}

button:active {
  border-width: 10vmin;
}