div{box-sizing: border-box;}

body{
  background-color: #f92d2d;
}
#main {
	padding-top: 60px;
	background-color: #f92d2d;
}
#main header {
	background: url(../img/header.png) center 0 no-repeat;
	height: 422px;
	width: 100%;
	margin: 0 auto;
  background-size: auto 100%;
}

.main {
	width: 1200px;
	margin: -72px auto 0;
  display: flex;
  justify-content: space-between;
}

.part-left{
  width: 300px;
}
.part-left .left-banner{
  height: 93px;
  width: 100%;
  background: url(../img/left-banner.png) 0/100% 100% no-repeat;
}
.part-left ul{
  border-top-right-radius: 20px;
  background-color: #fff;
  z-index: 99;
      margin-top: -20px;
}
.part-left ul li{
  padding: 0 16px;
  position: relative;
}
.part-left ul li .item{
  height: 90px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px dashed #dbdbdb;
}
.part-left ul li .teacher-intro{
  position: absolute;
  left: 310px;
  top: 0;
  width: 420px;
  padding: 10px;
  background-color: #fff;
  transition: all 0.5s ease-in-out;
  visibility: hidden;
  opacity: 0;
  border-radius: 10px;
  z-index: 999;
}
.part-left ul li .teacher-intro .banner{
  width: 400px;
  height: 100px;
  overflow: hidden;
  display: block;
  text-align: center;
}
.teacher-intro .banner img{
  margin: 0 -100%;
  height: 100%;
}
.part-left ul li:hover .teacher-intro{
  visibility: visible;
  opacity: 1;
}
.part-left ul li .teacher-intro:hover{
  display: block;
}
.part-left ul li:hover{
  background-color: #fff3db;
}

.part-left ul li .avatar{
  position: relative;
}
.part-left ul li .avatar .icon-v{
  position: absolute;
  height: 21px;
  width: 21px;
  display: inline-block;
  bottom: 0;
  right: 0;
  background: url(../img/icon-v.png) 0/contain no-repeat;
}
.part-left ul li .avatar img{
  width: 60px;
  height: 60px;
  border-radius: 50%;
}
.part-left ul li h4{
  font-weight: bold;
  font-size: 18px;
  color: #333;
}
.part-left ul li .content{width: 174px;}
.part-left ul li .content p{
  font-size: 14px;
  color: #f0433a;
  margin-top: 8px;
}
.part-left ul li .arrow{
  width: 8px;
  height: 14px;
  display: inline-block;
  background: url(../img/arrow.png) 0/contain no-repeat;
}
.teacher-intro .intro-wrap{
  display: flex;
  justify-content: space-around;
  margin-top: 10px;
}

.teacher-intro .intro-wrap .intro-avatar{
  width: 120px;
  height: 120px;
  border-radius: 50%;
}
.teacher-intro .intro-wrap .right-module{
  width: 240px;
}
.teacher-intro .intro-wrap .right-module h4{
  font-size: 18px;
  color: #333;
}
.teacher-intro .intro-wrap .right-module .button{
  font-size: 14px;
  color: #cd0d05;
  height: 23px;
  line-height: 23px;
  border: 1px solid #cd0d05;
  border-radius: 12px;
  padding: 0 10px;
  display: inline-block;
  margin: 10px 0;
}
.intro-wrap .right-module .button .detail{
  font-size: 14px;
  color: #666;
}

.part-right{
  width: 880px;
}

.part-right .class-wrap{
  width: 880px;
  /* height: 514px; */
  margin-bottom: 20px;
}
.part-right .class-wrap .head{
  height: 73px;
  width: 100%;
  background: url(../img/class-title.png) 0/100% 100% no-repeat;
  position: relative;
}
.tab-wrap{
  display: flex;
}
.tab-wrap .poster{
  height: 420px;
  width: 565px;
  background-color: #333;
  display: block;
}
.tab-wrap .poster img{
  height: 100%;
  width: 100%;
}
.tab-wrap .tab{
  width: 315px;
  background-color: #434343;
}
.tab-wrap .tab .tab-title{
  padding: 15px 20px 0;
  position: relative;
  height: 68px;
}
.tab .tab-title h4{
  color: #fff;
  font-size: 16px;
  line-height: 24px;
}
.tab .tab-title h4 span{
  color: #af2110;
  font-size: 14px;
  background-color: #fff3da;
  height: 20px;
  line-height: 20px;
  padding: 0 6px;
  border-radius: 10px;
  margin-left: 5px;
}
.tab-title p{
  color: #bbb;
  font-size: 14px;
  line-height: 20px;
}

.tab ul{
  height: 352px;
  overflow-y: auto;
  width: 100%;
}
.tab ul li{
  height: 68px;
  padding: 10px 0 0 20px;
  border-bottom: 1px solid #565656;
  cursor: pointer;
}
.tab ul li.cur{
  background-color: #333333;
}
.tab ul li .chap{
  font-size: 14px;
  line-height: 24px;
  color: #999;
}
.tab ul li .chap span{color: #fff;}
.tab ul li .title{color: #fff;font-size: 16px;font-weight: bold;line-height: 34px;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;}
.tab ul li.cur .title{color: #ff5a3c;}

.part-right .img-banner{width: 880px;margin: 0 0 20px;display: block; text-align: center; overflow: hidden;}
.part-right .img-banner img{width: 100%;}
#con_list {background-color: #fff;}
#con_list li{
  padding: 20px 0;
  width: 840px;
  margin: 0 20px;
  border-bottom: 1px solid #F0F2F6;
  display: flex;
  justify-content: space-between;
}
#con_list li .img-left{
  height: 110px;
  width: 166px;
  overflow: hidden;
}
#con_list li .img-left img{
  width: 166px;
  min-height: 110px;
}
#con_list li .txt-right{
  width: 640px;
}
#con_list li .txt-right:hover h3{
  color: #E22E35;
}
li .txt-right{
  font-size: 14px;
  color: #90969F;
  line-height: 20px;
}
li .txt-right h3{
  text-overflow : ellipsis;
  overflow: hidden;
  white-space: nowrap ;
  font-size: 18px;
  font-weight: bold;
  color: #333;
}
li .txt-right p{
  margin: 14px 0 8px;
  height: 40px;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}
.txt-right .info-wrap span{
  margin-right: 16px;
}
.txt-right .info-wrap .txt-name{
  color: #3B4355;
}

/* 扫码领红包：固定悬浮，不随页面滚动 */
.fixed-qrcode{
  position: fixed;
  right: max(10px, calc(50% - 725px));
  top: 225px;
  width: 118px;
  height: 150px;
  background: url(../img/hover.png) 0/contain no-repeat;
  z-index: 999;
}
.qr-code{
  width: 100px;
  height: 100px;
  margin: 8px auto;
  border-radius: 8px;
  display: block;
}

#main footer{
  text-align: center;
  padding: 60px 0 80px;
}
#main footer .f-tit{
  font-size: 18px;
  color: #ffd6d2;
  font-weight: bold;
  letter-spacing: 4px;
}
#main footer .f-info{
  font-size: 14px;
  color: #ff9d97;
  margin-top: 16px;
}