dabblet

.container {
	width: 800px;
	border: solid 1px #ccc;
	padding: 10px;
}

.container .box-fixed {
	width: 200px;	
	margin: 0 auto;	
	background-color: #2E99CD;
	padding: 50px;
	position: relative;
	
	margin-top: 50px;
}

.container .box-fixed::after {
	content: '';
	position: absolute;	
	bottom: 0;
	left: 0;
	height: 0px;
	width: 100px;
	border-top: 40px solid #0f0;
	border-left: 100px solid #fff;
	border-right: 100px solid #fff;
}

.container .box-fluid {
	width: 20%;
	margin: 0 auto;
	background-color: #2E99CD;
	padding: 50px;
	position: relative;
}

.container .box-fluid::after {
	content: '';
	position: absolute;
	bottom: 0;
	left: 0;
	height: 0px;
	width: 100%;
	
	border-top: 40px solid #0f0;
	border-left: 50% solid #f00;
	border-right: 50% solid #f00;
}