@charset "utf-8";
.clearfix:after {
  visibility: hidden;
  display: block;
  font-size: 0;
  content: " ";
  clear: both;
  height: 0;
}
.sidebar_left {
  float: left;
  width: 243px;
}
.sidebar_left .sidebar_list {
  width: 100%;
  height: auto;
  box-sizing: border-box;
  border-right: 1px solid #E2E6EF;
}
.sidebar_left .sidebar_list a {
  display: block;
  font-size: 16px;
  color: #7F8FA9;
  line-height: 21px;
}
.sidebar_left .sidebar_list .item {
  box-sizing: border-box;
  width: 242px;
  text-indent: 47px;
  position: relative;
}
.sidebar_left .sidebar_list .item a {
  padding-top: 20px;
  padding-bottom: 19px;
  position: relative;
}
.sidebar_left .sidebar_list .item a:before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 230px;
  height: 1px;
  background: #E2E6EF;
}
.sidebar_left .sidebar_list .item i {
  position: absolute;
  left: 16px;
  top: 28px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #7F8FA9;
}
.sidebar_left .sidebar_list .item .item_children_list {
  display: none;
}
.sidebar_left .sidebar_list .item_active .item_head {
  color: #3e7efe;
  font-weight: bold;
}
.sidebar_left .sidebar_list .item_active i {
  background: #3e7efe;
}
.sidebar_left .sidebar_list .item_active .item_children_list {
  display: block;
}
.sidebar_left .sidebar_list .item_children_subitem {
  box-sizing: border-box;
  width: 242px;
  height: 60px;
  position: relative;
}
.sidebar_left .sidebar_list .item_children_subitem a {
  padding-top: 20px;
  padding-bottom: 19px;
}
.sidebar_left .sidebar_list .item_children_active,
.sidebar_left .sidebar_list .item_children_subitem:hover {
  background: linear-gradient(90deg, rgba(255, 255, 255, 0) 0%, #ffffff 100%);
}
.sidebar_left .sidebar_list .item_children_active a,
.sidebar_left .sidebar_list .item_children_subitem:hover a {
  color: #3e7efe;
}
.container_wrap {
  padding-top: 50px;
  padding-bottom: 60px;
  min-width: 1180px;
  overflow: hidden;
}
body {
  background: #F9FAFF;
}
.main_content {
  float: right;
  box-sizing: border-box;
  width: 878px;
  height: auto;
}
.course_moduler {
  width: 100%;
}
.course_moduler .main_body {
  width: 100%;
}
.course_moduler .list {
  width: 912px;
}
.course_moduler a {
  display: block;
}
.course_moduler .item {
  float: left;
  width: 270px;
  height: 160px;
  position: relative;
  box-sizing: border-box;
  margin-right: 34px;
  margin-bottom: 36px;
  overflow: hidden;
  cursor: pointer;
}
.course_moduler .item .img {
  width: 270px;
  height: 160px;
}
.course_moduler .item .img img {
  width: 100%;
  height: 100%;
}
.course_moduler .item .item_dl {
  position: absolute;
  top: 70px;
  width: 100%;
  box-sizing: border-box;
  padding: 33px 20px 0 20px;
  transition: all .35s linear;
  -o-transition: all .35s linear;
  -webkit-transition: all .35s linear;
  -moz-transition: all .35s linear;
  -ms-transition: all .35s linear;
}
.course_moduler .item .item_title {
  font-size: 16px;
  font-weight: bold;
  color: #FFFFFF;
  line-height: 21px;
}
.course_moduler .item .item_name {
  margin-top: 4px;
  font-size: 14px;
  color: #FFFFFF;
  line-height: 19px;
}
.course_moduler .item .item_detail {
  margin-top: 10px;
  max-height: 48px;
  font-size: 12px;
  color: #FFFFFF;
  line-height: 16px;
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 3;
  overflow: hidden;
  text-overflow: ellipsis;
  word-break: break-all;
}
.course_moduler .item .item_mask {
  transition: all .35s linear;
  -o-transition: all .35s linear;
  -webkit-transition: all .35s linear;
  -moz-transition: all .35s linear;
  -ms-transition: all .35s linear;
  position: absolute;
  top: 70px;
  border-left: 270px solid #000;
  border-left: 270px solid rgba(0, 0, 0, 0.3);
  border-top: 45px solid transparent;
  height: 90px;
}
.course_moduler .item:hover .item_mask {
  top: -45px;
  border-left-color: rgba(0, 0, 0, 0.7);
  height: 205px;
}
.course_moduler .item:hover .item_dl {
  top: 0;
}
