.arrow_box {
	position: relative;
	background: #000000;
	width:
}
.arrow_box:after {
width:100%;
	top: 100%;
	left: 50%;
	border: solid transparent;
	content: " ";
	height: 0;
	width: 0;
	position: absolute;
	pointer-events: none;
	border-color: rgba(0, 0, 0, 0);
	border-top-color: #000000;
	border-width: 30px;
	margin-left: -30px;
}