JSFiddle - React, Tailwind, and code Playground

HTML

<div>BUTTON</div>

CSS

div {
  position: relative;
  display: inline-block;
  background: #ffffff;
  border: 5px solid #31302B;
  color: #31302B;
  padding: 12px 17px;
  margin: 25px;
  font-family: 'OpenSansBold', sans-serif;
  border: 3px solid #31302B;
  font-size: 14px;
  font-weight: bold;
  letter-spacing: 1px;
  text-transform: uppercase;
  border-radius: 2px;
  background-image: linear-gradient(#31302B, #31302B);
  background-position: 100% 0;
  background-repeat: no-repeat;
  background-size: 0% 100%;
  transition: background-size .5s, color .5s;
  transform-origin: left;
}
div:hover {
  background-size: 100% 100%;
  color: #ffffff;
  background-position: 0 100%;
}