JSFiddle - React, Tailwind, and code Playground

HTML

<div class = 'object'></div>

CSS

body {
	margin:				75px;
	background:			#f0fff0;
}

.object {
	position:			relative;
	
	width:				300px;
	height:				0px;
	
	border-left:		50px solid transparent;
	border-right:		50px solid transparent;
	border-bottom:		100px solid red;
	
	background: 		transparent;
}

.object:after {
	content:			'';
	
	position:			absolute;
	top:				2px;
	left:				calc(2.45px - 50px);
	
	
	width:				calc(300px - 2 * 1.4px);
	height:				0px;
	
	border-left:		49px solid transparent;
	border-right:		49px solid transparent;
	border-bottom:		calc(100px - 2px) solid white;
	
	background: 		transparent;
	
}