.nav_column .nav_adv3{
	height: 170px;
	margin-bottom: 15px;
	overflow: hidden;
}
.nav_column .nav_adv3 ul{

}
.nav_column .nav_adv3 ul li{
	height: 170px;
}
.nav_column .nav_adv3 img{
	vertical-align: center;
	width:100%;
	height:100%;
}

.nav_adv_m{
	display: none;
}
@media screen and (max-width:768px) {
	.nav_top{
		display: none;
	}
	.nav_adv_m{
	display: block;
	}
	.nav_adv_m img{
	width: 100%;
	}
}