JSFiddle - React, Tailwind, and code Playground

HTML

<div class="leaf"></div>

CSS

.leaf { 
  width: 100px; height: 100px;
  background-color: #A0DE21; 
  -moz-border-radius: 100px 0px;
  -webkit-border-radius: 100px 0px;
  border-radius: 100px 0px;
}