*{
	margin: 0;
	padding: 0;
}
ul li{
	list-style-type: none;
}
a{
	text-decoration: none;
	color: black;
}
body{
	background: #f1f0f0;
}
.hide{
	display: none;
}
/*头部*/
#header{
	display: flex;
	justify-content: center;
	width: 100%;
	background: #fff;
}
#header img{
	margin-left: -18px;
}
#header-nav{
	display: flex;
	margin-left: 16px;
	align-items: center;
}
#header-nav li{
	height: 100%;
}
#header-nav li a{
	display: flex;
	height: 100%;
	align-items: center;
	font-size: 20px;
	padding: 0 12px;
	
}
#header-nav a:hover{
	background: #249fe5;
	color: #ffffff;
}

/*内容*/
#content{
	width: 1000px;
	height: 1200px;
	margin:18px auto 0;
}
	/*左*/
	.content_left{
		float: left;
		width: 240px;
		height: 1200px;
		
		display: flex;
		flex-direction: column;
	}
		.left_above{
			height: 576px;
			background:#fff;
		}
			.left_above p:first-child,.left_middle p:first-child{
				background: url(../img/photo_01.png) no-repeat 15px 12px;
				background-color: #249fe5;
				background-size: 24px;
				height: 48px;
			}
			.teaching_conter,.teaching_effectiveness{
				margin-left:50px;
				line-height: 45px;
				color:#fff;
				font-size: 20px;
			}
			.conter_above{
				height: 36px;
				width: 90%;
				line-height: 36px;
				padding-left:10%;
				background: #f39900;
				color:#fff;
				font-size: 18px;
			}
			.Teaching_team{
				background:#fff;
			}
			.Teaching_team img{
				margin:14px 12px 10px;
				width: 210px;
				height: 140px;
				width: 90%;
			}
			.Teaching_team div{
				margin:0 15px;
				padding-bottom: 16px;
				font-size: 16px;
				display: flex;
				justify-content: space-between;
			}
			.Course_outline{
				width: 100%;
				height: 50px;
				background: #f39900;
				line-height: 50px;
				border-bottom: 1px solid #e4e4e4;
				border-top: 1px solid #e4e4e4;
			}
		.Course_outline a{
			display: block;
			background: #fff;
			height: 100%;
			width:95%;
			float:right;
			padding-left: 5px;
			font-size: 18px;
		}
			.name_block{
				height: 239px;
				width: 100%;
				overflow-y:auto;
			}
			.name_block li{
				border-bottom:1px solid #e4e4e4;
				background: #fff;
				display: flex;
				flex-direction: column;
			}
				.subject:hover{
					cursor:pointer;
					background: #eee;
				}
				.subject span:nth-child(1){
					font-size: 16px;
					margin-left: 7px;
					padding-top: 10px;
					
				}
				.subject span:nth-child(2){
					font-size: 16px;
					width:10px;
					height: 10px;
					margin-left: 212px;
					margin-top: -24px;
					padding-bottom: 25px;
				}
				
				.task a{
					display: block;
					font-size: 14px;
					background: #fef1da;
					border-bottom: 1px solid #e4e4e4;
					line-height: 38px;
					padding-left:10px;
					height: 38px;
				}
				.task{
					display: none;
				}
		.left_middle{
			margin-top: 20px;
			height: 210px;
			background: #ffffff;
		}
			.effectiveness_style{
				height: 60px;
				width: 80%;
				background:#fff;
				display: block;
				margin:0 auto;
				border-bottom: 1px solid #ccc;
				font-size: 18px;
			}
			.effectiveness_style img{
				float: left;
				margin:26px 15px 22px 2px;
			}
			.effectiveness_style span{
				float: left;
				line-height: 60px;
			}
		.left_below{
			margin-top: 20px;
			height: 203px;
			
		}
	/*右*/
	.content_right{
		float:right;
		width: 740px;
		height: 1200px;
		background: #ffffff;
	}
		.right_above{
			height: 478px;
			background: #fff;
			border: 1px dotted #999;	
			
		}
			h2{
				height:48px;
				background:  #249fe5;
				font-size: 20px;
				color: #fff;
				font-weight: normal;
				line-height: 48px;
				width: 97%;
				padding-left: 3.2%;
			}
			.Courseware {
				width: 96%;
				margin:0 auto;
				height: 110px;
				padding-top: 20px;
				padding-left: 2%;
				border-bottom: 1px dotted #999;
				text-indent: 2em;
				font-size: 16px;
				line-height: 26px;
			}
			.right_above div>a,.right_middle div>a{
				margin-left: 20px;
			}
			.right_above img{
				margin:26px 76px;
				height: 258px;
				width: 190px;
				float:left;
			}
			.Explain{
				padding-top: 32px;
				float:left;
				width: 388px;
				height: 276px;
				font-size: 16px; 
			}
		.right_middle{
			float: left;
			height: 703px;
			background: #fff;
			border:1px solid #999;
		}
			.movie{
				width: 246px ;
				height: 190px;
				margin-top: 10px;
				float: left;

			}
			.movie_a{
				height: 150px;
				width: 220px;
				margin: 5px 10px;
			}
			.movie div{
				margin-left: 6px;
				width: 235px;
				font-size: 16px;
			}
			.down{
				float: right!important;
			}
			#movie_one,#movie_two,#movie_three{
				width: 222px;
				height: 152px;
			}
		/*视频*/
		.Mask {
			background: rgba(0,0,0,.5);
			position:fixed;
			z-index: 2;
			top: 0;
			left: 0;
			right: 0;
			bottom: 0;
		}
		#Close{
			width: 21px;
			height: 19px;
			border:1px solid #999;
			z-index: 4;
			text-align: center;
			display: block;
			position:absolute;
			bottom: 78.4vh;
			left: 143.7vh;
			cursor:pointer;
		}
		video{
			background:#fff;
			width: 935px;
			height: 590px;
			position:absolute;
			z-index: 3;
			bottom: 20vh;
			left: 50vh;
		}
		
/*底部*/
#footer{
	height: 370px;
	width: 100%;
	background: #202323;
	color: #9a9a9a;
	display: flex;
	justify-content: center;
	flex-direction: column;
}
.footer_nav{
	border-bottom: 1px solid #9A9A9A;
	height: 70%;
	width: 1000px;
	position: relative;
	margin:0 auto;
}
.footer_nav li:nth-child(1){
	position: absolute;
	left: 0;
	top: 20%;
	font-size: 30px;
}
.footer_nav li:nth-child(2){
	position: absolute;
	left: 0;
	top: 40%;
	
}
.footer_nav li:nth-child(3){
	position: absolute;
	left: 0;
	top: 50%;
	
}
.footer_nav li:nth-child(4){
	position: absolute;
	left: 0;
	top: 60%;
}
.footer_nav li:nth-child(5){
	position: absolute;
	left: 44.7%;
	top: 32%;
}
.footer_nav li:nth-child(6){
	position: absolute;
	right: 0;
	top: 30%;
}
.footer_nav img{
	width: 100%;
}
#footer-title{
	margin:0 auto;
}