.course-body {
  background: #f5f5f4;
  padding: 25px  0 30px;
}
.course-body .wrapper {
  width: 1200px;
  margin: 0 auto;
}
.course-body .main-content {
  width: 840px;
  background: #fff;
  min-height: 400px;
  float: left;
  border: 1px solid #eaeae6;
  border-radius: 4px;
}
.course-body .sidebar {
  width: 320px;
  float: right;
}
.course-body .tab-nav {
  height: 53px;
  position: relative;
  width: 838px;
  z-index: 100;
}
.course-body .tab-nav a {
  font-size: 18px;
  padding: 0 20px;
  height: 53px;
  line-height: 53px;
  text-align: center;
  position: relative;
  display: inline-block;
  color: #848a90;
}
.course-body .tab-nav a.active {
  color: #36404a;
  font-weight: 600;
}
.course-body .tab-nav a.active::after {
  content: '';
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  top: 47px;
  width: 14px;
  height: 3px;
  background: #fb4a3e;
  border-radius: 100px;
}
.course-body .tab-nav.fixed {
  width: 100%;
  height: 70px;
  line-height: 70px;
  box-shadow: 0 0 8px rgba(0, 0, 0, 0.4);
}
.course-body .tab-nav.fixed .inner-wrap {
  width: 1200px;
  margin: 0 auto;
  background: #f5fafa;
  position: relative;
}
.course-body .tab-nav.fixed .inner-wrap .active {
  background: transparent;
}
.course-body .tab-nav.fixed .course-price {
  display: block;
}
.course-body .course-tab-bd {
  overflow: hidden;
}
.course-body .course-tab-bd .catalog-tab-hd {
  padding: 30px 0 30px;
  font-size: 16px;
  border-bottom: 1px solid #eeeeee;
}
.course-body .course-tab-bd .catalog-tab-hd a {
  font-size: 18px;
  margin-right: 30px;
  color: #adc5c1;
  border: 1px solid #adc5c1;
  padding: 4px 20px;
  border-radius: 4px;
}
.course-body .course-tab-bd .catalog-tab-hd a i {
  font-size: 18px;
  color: #a6a6a6;
}
.course-body .course-tab-bd .catalog-tab-hd a.active {
  color: #1cc16d;
  border: 1px solid #1cc16d;
}
.course-body .why-choose-youdao {
  width: 100%;
  border-top: 1px solid #eaeae6;
  background: #fdfdfd;
  margin: 30px 0 0;
  padding-bottom: 65px;
}
.course-body .why-choose-youdao h1 {
  color: #455056;
  font-size: 18px;
  margin: 30px 0 15px;
  text-align: center;
}
.course-body .why-choose-youdao ins {
  display: block;
  height: 4px;
  margin: 0 auto;
  width: 70px;
  background: #fb4a3e;
}
.course-body .why-choose-youdao ul {
  text-align: center;
}
.course-body .why-choose-youdao ul li {
  display: inline-block;
  width: 140px;
  margin: 40px 17px 0;
  line-height: 1.5;
}
.course-body .why-choose-youdao ul li img {
  display: inline-block;
}
.course-body .why-choose-youdao ul li h3 {
  font-size: 16px;
  color: #455056;
  margin: 18px 0 8px;
}
.course-body .why-choose-youdao ul li p {
  font-size: 12px;
  color: #455056;
}
.course-body .tab-nav .inner em {
  background: #FF9830;
  color: #fff;
  width: 26px;
  height: 16px;
  position: absolute;
  top: 8px;
  right: -10px;
  line-height: 15px;
  font-size: 12px;
  padding: 0 2px;
  box-sizing: content-box;
  text-align: center;
  border-radius: 2px;
}
.course-body .course-price {
  position: absolute;
  right: 0;
  top: 0;
  z-index: 55;
  display: none;
}
.course-body .course-price em {
  font-size: 24px;
  color: #ff614c;
  margin-right: 14px;
}
.course-body .course-price a {
  height: 38px;
  line-height: 38px;
  width: 180px;
  display: inline-block;
  *display: inline;
  zoom: 1;
  font-size: 22px;
  color: #f7f7f7;
  border-radius: 4px;
}
.dialog {
  display: none;
}
.dialog .Dialogmask {
  position: fixed;
  z-index: 999;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(0, 0, 0, 0.6);
}
.dialog .Dialogwrapper {
  position: fixed;
  width: 440px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  -ms-transform: translate(-50%, -50%);
  -moz-transform: translate(-50%, -50%);
  -webkit-transform: translate(-50%, -50%);
  -o-transform: translate(-50%, -50%);
  padding: 0 40px;
  border-radius: 4px;
  background-color: #fff;
  z-index: 1000;
  font-size: 18px;
  text-align: center;
}
.dialog .Dialogwrapper .dialogContent {
  margin-top: 74px;
  margin-bottom: 50px;
}
.dialog .Dialogwrapper .dialogContent p {
  line-height: 30px;
}
.dialog .Dialogwrapper .dialogBtn {
  display: inline-block;
  border-radius: 100px;
  padding: 11px 25px;
  margin-bottom: 30px;
  cursor: pointer;
  margin-right: 20px;
  color: #fff;
  background-color: #0db55d;
  width: 124px;
}
.dialog .Dialogwrapper .dialogBtn:hover {
  background-color: #e2311c;
}
.dialog .Dialogwrapper .dialogBtn:last-child {
  margin-right: 0;
}
.dialog .Dialogwrapper .dialogBtn.grey {
  background-color: #ccc;
}
.dialog .Dialogwrapper .dialogBtn.grey:hover {
  background-color: #bfbfbf;
}