JSFiddle - React, Tailwind, and code Playground

by Casufi

HTML

<div>sale</div>

CSS

div{
  width: 150px;
  height: 150px;
  background-color: #999;
  border-top: -150px solid white;
  border-left: -150px solid white;
  border-bottom: -150px solid white;
}