.course {
  padding-top: 80px;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 99;
  background-color: #fff;
  overflow-x: hidden;
  overflow-y: auto;
  width: 1200px;
  height: 100vh;
}
.course .head {
  width: 1200px;
  height: 80px;
  position: fixed;
  top: 0;
  left: 50%;
  margin-left: -600px;
  z-index: 20;
  background-color: #fff;
}
.course .head .w-course {
  height: 80px;
}
.w-course {
  margin: 0 120px;
}

.c-l-title {
  font-size: 24px;
  color: #000000;
  line-height: 41px;
}

.c-l-con {
  font-family: AlibabaPuHuiTi-Regular;
  font-size: 14px;
  color: #000000;
}

.course-1 {
  margin-top: 60px;
}

.course-1 .left {
  position: relative;
}

.course-1 .left .bg-1 {
  width: 220px;
  height: 71px;
  position: absolute;
  background: url(../image/course-1-01.png);
  top: 17px;
  left: 41px;
}

.course-1 .right {
  width: 526px;
  line-height: 26px;
}

.course-1-pic {
  width: 1200px;
  height: 681px;
  margin-top: 70px;
}

.course-1-pic img {
  width: 100%;
}

.course-2 {
  height: 1350px;
  background-color: #DCEFFC;
}

.course-2 h3 {
  text-align: center;
  font-size: 24px;
  color: #0064ce;
  padding: 50px 0 40px 0;
}

.course-2 .boxflex {
  flex-wrap: wrap;
}

.course-2 .bi_item {
  width: 30%;
  margin-right: 5%;
}

.course-2 .xuan_item {
  width: 23%;
  margin-right: 2.6%;
}

.course-2 .ke_item_item_tags {
  border-top: 2px solid #52b1f0;
}

.course-2 .ke_item_item_tags .item-1 {
  font-size: 18px;
  color: #52b1f0;
  margin: 15px 0;
  font-family: AlibabaPuHuiTi-Regular;
}

.course-2 .ke_item_item_tags .item-2 {
  font-size: 13px;
  color: #3e3a39;
  line-height: 25px;
  font-family: AlibabaPuHuiTi-Regular;
}

.course-2 .xuan_item .item-2 {
  margin-bottom: 10px;
  line-height: 23px;
}
.course-2 .ke_item_item_tags .item-3-02 ul {
  width: 50%;
}
.course-2 .ke_item_item_tags .item-3 ul li {
  font-size: 13px;
  color: #595757;
  line-height: 23px;
  font-family: AlibabaPuHuiTi-Regular;
}

.course-2 .ke_item_item_tags .item-3 ul li span {
  display: inline-block;
  margin-right: 3px;
  color: #fe4800;
}

.course-2 .ke_desc {
  display: flex;
  margin-top: 75px;
}

.course-2 .ke_desc div {
  font-size: 11px;
  color: #3e3a39;
  line-height: 21px;
  font-family: AlibabaPuHuiTi-Regular;
}

.course-title {
  font-size: 24px;
  color: #0064ce;
  text-align: center;
  padding: 60px 0 40px 0;
}

.course-3 .item-1,
.course-4 .item-1 {
  width: 41%;
  height: 395px;
  margin-right: 2%;
}

.course-3 .item-1 .text {
  width: 340px;
  height: 127px;
  font-size: 16px;
  color: #3e3a39;
}

.course-4 .item-1 .text {
  width: 340px;
  height: 145px;
  font-size: 16px;
  color: #3e3a39;
}

.course-3 .item-2,
.course-4 .item-2 {
  width: 27.5%;
  height: 395px;
  margin-right: 2%;
}

.course-3 .item-2 .pic-2,
.course-4 .item-2 .pic-2 {
  margin-bottom: 11px;
}

.course-5 {
  height: 663px;
  background-color: #DCEFFC;
}

.course-5 .left-item {
  font-family: AlibabaPuHuiTi-Light;
  width: 241px;
  font-size: 16px;
  line-height: 29px;
  color: #3e3a39;
}

.course-5 .right-item {
  width: 675px;
}
.course-5 .right-item .item-1 {
  display: flex;
}
.course-5 .right-item .plan_tags_item {
  padding-left: 10px;
  border-left: 1px dashed #0064ce;
  width: 25%;
}
.course-5 .right-item .plan_tags_item h4 {
  font-family: AlibabaPuHuiTi-Regular;
  height: 30px;
  font-size: 15px;
  color: #0064ce;
}
.course-5 .right-item .plan_tags_item dl dt {
  font-family: AlibabaPuHuiTi-Regular;
  font-size: 13px;
  color: #000000;
  margin-top: 8px;
  line-height: 20px;
}
.course-5 .right-item .plan_tags_item dl dd {
  font-family: AlibabaPuHuiTi-Regular;
  font-size: 11px;
  color: #595757;
  line-height: 20px;
}
.course-5 .right-item .item-2 {
  margin-top: 20px;
}
.course-5 .right-item .item-3 {
  margin-top: 20px;
  color: #3e3a39;
  font-size: 10px;
  font-family: AlibabaPuHuiTi-Regular;
}
.course-6 .item-1{
  font-size: 14px;
  color: #000000;
  margin-top: -20px;
  margin-bottom: 40px;
  text-align: center;
  font-family: AlibabaPuHuiTi-Regular;
}
.course-6 .item-2 {
  font-size: 16px;
  line-height: 27px;
  color: #3e3a39;
}
.course-6 .item-3 {
  margin: 30px 0;
}
@media (min-width:750px){
  .m_course-nav {
    display: none;
  }
  .m_course-1-pic {
    display: none;
  }
  .course-2 .bi_item {
    height: 310px;
  }
  .course-2 .bi_item:nth-of-type(3n) {
    margin-right: 0;
  }
  .course-2 .xuan_item {
    height: 395px;
  }
  .course-2 .xuan_item:nth-of-type(4) {
    margin-right: 0;
  }
  .course-5 {
    margin-top: 90px;
  }
}
@media screen and (max-width: 750px) {
  .course {
    width: 100%;
    padding-bottom: 180px;
  }
  .w-course {
    margin: 0;
    width: 100%;
  }
  .course .head {
    width: 100%;
    height: 80px;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    margin-left: 0;
    z-index: 20;
    background-color: #fff;
  }
  .course .head .w-course {
    padding: 0 5%;
  }
  .course-nav {
    display: none;
  }
  
  .c-l-con {
    font-size: 12px;
  }
  
  .course-1 {
    margin-top: 30px;
  }
  
  .course-1 .left {
    position: relative;
  }
  
  .course-1 .left .bg-1 {
    width: 220px;
    height: 71px;
    position: absolute;
    background: url(../image/course-1-01.png);
    top: 17px;
    left: 41px;
  }
  
  .course-1 .right {
    font-size: 13px;
    width: 100%;
    line-height: 21px;
    margin-top: 30px;
  }
  .course-1-pic {
    display: none;
  }
  .m_course-1-pic {
    width: 100%;
    margin-top: 40px;
  }
  
  .m_course-1-pic img {
    width: 100%;
  }
  
  .course-2 {
    height: auto;
    background-color: #DCEFFC;
    padding-bottom: 40px;
  }
  
  .course-2 h3 {
    text-align: center;
    font-size: 24px;
    color: #0064ce;
    padding: 40px 0 20px 0;
  }
  
  .course-2 .boxflex {
    flex-wrap: wrap;
  }
  
  .course-2 .bi_item {
    width: 44%;
    margin:0 3%;
  }
  .course-2 .bi_item:nth-child(1),.course-2 .bi_item:nth-child(2){
    height: 300px;
  }
  .course-2 .bi_item:nth-child(3),.course-2 .bi_item:nth-child(4){
    height: 270px;
  }
  .course-2 .bi_item:nth-child(5),.course-2 .bi_item:nth-child(6){
    height: 300px;
  }
  .course-2 .xuan_item {
    width: 44%;
    margin: 3%;
  }
  .course-2 .xuan_item:nth-child(1),.course-2 .xuan_item:nth-child(2){
    height: 400px;
  }
  .course-2 .xuan_item:nth-child(3),.course-2 .xuan_item:nth-child(4){
    height: 340px;
  }
  .course-2 .ke_item_item_tags {
    border-top: 2px solid #52b1f0;
  }
  
  .course-2 .ke_item_item_tags .item-1 {
    font-size: 16px;
    color: #52b1f0;
    line-height: 30px;
  }
  
  .course-2 .ke_item_item_tags .item-2 {
    font-size: 12px;
    color: #3e3a39;
    line-height: 18px;
  }
  
  .course-2 .xuan_item .item-2 {
    margin-bottom: 10px;
    line-height: 18px;
  }
  
  .course-2 .ke_item_item_tags .item-3 ul li {
    font-size: 11px;
    color: #595757;
    line-height: 17px;
  }
  
  .course-2 .ke_item_item_tags .item-3 ul li span {
    display: inline-block;
    margin-right: 3px;
    color: #fe4800;
  }
  
  .course-2 .ke_desc {
    display: flex;
    margin-top: 30px;
  }
  
  .course-2 .ke_desc div {
    font-size: 9px;
    color: #3e3a39;
    line-height: 15px;
  }
  
  .course-title {
    font-size: 24px;
    color: #0064ce;
    text-align: center;
    padding: 40px 0 30px 0;
  }
  
  .course-3 .item-1,
  .course-4 .item-1 {
    width: 100%;
    height: auto;
    margin-right: 0;
  }
  
  .course-3 .item-1 .text {
    width: 100%;
    height: auto;
    font-size: 13px;
    color: #3e3a39;
    margin-bottom: 30px;
  }
  
  .course-4 .item-1 .text {
    width: 100%;
    height: auto;
    font-size: 13px;
    color: #3e3a39;
    margin-bottom: 30px;
  }
  
  .course-3 .item-2,
  .course-4 .item-2 {
    width: 48%;
    height: auto;
    margin-right: 4%;
    margin-top: 11px;
  }
  .course-3 .item-2-01,
  .course-4 .item-2-01 {
    margin-right: 0;
  }
  .course-3 .item-2 .pic-2,
  .course-4 .item-2 .pic-2 {
    margin-bottom: 11px;
  }
  
  .course-5 {
    margin-top: 40px;
    height: auto;
    background-color: #DCEFFC;
    padding-bottom: 30px;
  }
  
  .course-5 .left-item {
    font-family: AlibabaPuHuiTi-Light;
    width: 100%;
    font-size: 13px;
    line-height: 21px;
    color: #3e3a39;
  }
  
  .course-5 .right-item {
    width: 100%;
    margin-top: 30px;
  }
  .course-5 .right-item .item-1 {
    display: flex;
  }
  .course-5 .right-item .plan_tags_item {
    padding: 0 10px;
    border-left: 1px dashed #0064ce;
    width: 25%;
  }
  .course-5 .right-item .plan_tags_item h4 {
    height: 20px;
    font-size: 13px;
    color: #0064ce;
  }
  .course-5 .right-item .plan_tags_item dl dt {
    font-size: 13px;
    color: #000000;
    margin-top: 8px;
    line-height: 20px;
  }
  .course-5 .right-item .plan_tags_item dl dd {
    font-size: 10px;
    color: #595757;
    line-height: 16px;
  }
  .course-5 .right-item .item-2 {
    margin-top: 20px;
  }
  .course-5 .right-item .item-3 {
    margin-top: 20px;
    color: #3e3a39;
    font-size: 10px;
  }
  .course-6 .item-1{
    font-size: 14px;
    color: #000000;
    margin-top: -20px;
    margin-bottom: 20px;
    text-align: center;
  }
  .course-6 .item-2 {
    font-size: 13px;
    line-height: 21px;
    color: #3e3a39;
  }
  .course-6 .item-3 {
    margin: 30px 0;
  }
}