#cont_int_der
{
	
	padding-bottom:5px;
	margin-bottom:5px;
	
	border-top-style:none;
	border-left-style:none;
	border-right-style:none;
	border-bottom-width: 1px;
	border-bottom-style: solid;
	border-bottom-color: #aaa;
	float:left;
	width:240px;
}