html, body {
	width: 100%;
	height: 100%;
	font-family: "Microsoft Yahei", Tahoma, Arial, sans-serif;
	background-image:url(../images/bg.jpg?v=1.3);
	background-position:top ;
	background-size:120%;
	background-repeat: no-repeat;
	text-align: center;
    overflow:hidden;
}
a{
  text-decoration:none;
}
.btn-download, .mobile-btn-download {
	height: 40px;
	line-height: 40px;
	color: #fff;
	border-radius: 3px;
	font-size: 16px;
	background-color:#1E70A8;
	padding:10px 15px;
}
.btn-download:visited, .mobile-btn-download:visited {
	color: #fff;
}
.mobile-btn-download {
	font-size: 14px;
	text-align: center;
	margin: 0 auto;
	margin-bottom: 12px;
	padding:10px 20px;
}

.intro-title {
	font-size:21px;
	font-weight: normal;
	margin:310px 0 16px;
	color: #FFFFFF;
}
.mask {
	position: absolute;
	width: 100%;
	height: 100%;
	left: 0;
	top: 0;
	background-color: rgba(0, 0, 0, .6);
	z-index: 999;
	display: none;
}
.mask::before {
 content: "";
 position: absolute;
 right: 20px;
 top: 5px;
 width: 200px;
 height: 80px;
 background: url("../images/wechat.png") no-repeat;
 background-size: contain;
}