#content{
			width: 50%;
			position: absolute;
			left: 25%;
			background-color: #444444;
			height: 800px;
		}
		#heading{
			width: 70%;
			margin-left: -30px;
			background-color: #cccccc;
			padding: 10px;
			position: relative;
		}
		#triangle{
			border-color: black;
			border-style: solid;
			line-height: 0;
			border: 0 solid transparent;/*Default*/
			border-left: 30px solid transparent;
			border-top: 15px solid #999999;
			top: 100%;
			left: 0;
			position: absolute;
		}

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CSS