.link_back1 a{

	text-decoration:none;

	color:#fff;

}

.link_back a{

	text-decoration:none;

	color:#333;

}

.login_back{

	margin-top:30px;

}



.logo_back{

	width:70px;

	height:70px;

	margin-top:-50px;

	

}



.div_back{

	border:1px solid #ccc;

	margin:10px;

	padding:10px;

	

}

.banner{

	width:100%;

	height:200px;

	border:2px solid #ccc;

	margin:10px;

}



 @media screen and (max-width:768px){

	background:url('../img/b2.jpg');

	background-size:cover;

}