.dooroad_us{
	height: 1800px;
    width: 1200px;
    margin: 0 auto;
    overflow: hidden;
}

.picture1{
	width:1200px;
	height:500px;
	text-align:center;
	position:relative;
}

.picture2{
	width:1200px;
	height:500px;
	text-align:center;
}

.lessence{
	width:600px;
	height:900px;
}

.Transparent{
	width:800px;
	height:200px;
	position:absolute;
	top:170px;
	left:220px;
	background:black;
	opacity:0.6;
}

.introduction{
	width:750px;
	height:150px;
	position:absolute;
	font-size:17;
	top:30px;
	left:20px;
	color:white;
	line-height:40px;
}