body {
  margin: 0;
  padding: 0;
}
.clean {
  clear: both;
}
.container1 {
  padding-bottom: 36px;
}
.container1 .banner {
  display: block;
  width: 100%;
}
.container1 .subject {
  max-width: 1180px;
  margin: 0 auto;
  position: relative;
}
.container1 .subject .title {
  margin-top: 60px;
  margin-bottom: 35px;
  vertical-align: middle;
  text-align: center;
  position: relative;
}
.container1 .subject .title img {
  display: block;
  width: 100%;
}
.container1 .subject .title .isMb {
  display: none;
}
.container1 .subject .videoCont {
  width: 100%;
  border-bottom: 3px solid #b1b1b1;
  margin-bottom: 40px;
}
.container1 .subject .videoCont .nav {
  height: 38px;
  margin-bottom: 25px;
}
.container1 .subject .videoCont .nav .question_Nav {
  float: left;
  height: 100%;
  width: 33.2%;
  margin-right: 0.2%;
  cursor: pointer;
  box-sizing: border-box;
  padding-left: 16px;
  background: url('images/choosed.png') left top no-repeat;
}
.container1 .subject .videoCont .nav .question_Nav .font {
  line-height: 29px;
  color: #f8f8f8;
  font-size: 18px;
}
.container1 .subject .videoCont .nav .panel_Nav {
  float: left;
  width: 33.2%;
  height: 100%;
  margin-right: 0.2%;
  cursor: pointer;
  box-sizing: border-box;
  padding-left: 16px;
  background: url('images/nochoose.png') left top no-repeat;
}
.container1 .subject .videoCont .nav .panel_Nav span {
  line-height: 29px;
  color: #f8f8f8;
  font-size: 18px;
}
.container1 .subject .videoCont .nav .operation_Nav {
  float: left;
  height: 100%;
  width: 33.2%;
  cursor: pointer;
  box-sizing: border-box;
  padding-left: 16px;
  background: url('images/nochoose.png') left top no-repeat;
}
.container1 .subject .videoCont .nav .operation_Nav span {
  line-height: 29px;
  color: #f8f8f8;
  font-size: 18px;
}
.container1 .subject .videoCont .panel,
.container1 .subject .videoCont .operation {
  display: none;
}
.container1 .subject .videoCont .videoItem {
  width: 32%;
  float: left;
  margin-right: 2%;
}

.container1 .subject .videoCont .videoItem p{
  font-size: 16px;
  cursor: pointer;
}
.container1 .subject .videoCont .videoItem .imgCont {
  position: relative;
}
.container1 .subject .videoCont .videoItem .imgCont img {
  width: 100%;
  display: block;
}
.container1 .subject .videoCont .videoItem .imgCont .popup {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  background: rgba(0, 0, 0, 0.2);
}
.container1 .subject .videoCont .videoItem .imgCont .popup .playCont {
  height: 100%;
  width: 100%;
  position: relative;
}
.container1 .subject .videoCont .videoItem .imgCont .popup .playCont img {
  position: absolute;
  cursor: pointer;
  width: 22.92%;
  left: 50%;
  top: 50%;
  margin-left: -11.46%;
  margin-top: -11.46%;
}
.container1 .subject .videoCont .videoItem p {
  margin: 15px 0 44px 0;
}
.container1 .subject .videoCont .videoItem:nth-child(3n+3) {
  margin-right: 0;
}
.container1 .subject img {
  width: 100%;
  display: block;
}
.container1 .subject .isMb {
  display: none;
}
.container1 .subject .btnCont {
  position: absolute;
  bottom: 37px;
  right: 451px;
}
.container1 .subject .btnCont .caozuo {
  display: block;
  width: 100%;
  margin-bottom: 25px;
}
.container1 .subject .btnCont .btn {
  display: block;
  width: 100%;
}
.container1 .popupDiv {
  position: fixed;
  background: rgba(4, 11, 24, 0.93);
  height: 100%;
  width: 100%;
  top: 0;
  left: 0;
  display: none;
}
.container1 .popupDiv .iframeDiv {
  position: fixed;
  top: 15%;
  left: 10%;
  height: 70%;
  width: 80%;
}
.container1 .popupDiv .iframeDiv img {
  position: absolute;
  width: 50px;
  right: -50px;
  cursor: pointer;
  top: -50px;
}
.container1 .isMb {
  display: none;
}
@media screen and (max-width: 1180px) {
  .subject {
    padding-left: 10px;
    padding-right: 10px;
  }
}
@media screen and (max-width: 768px) {
  .isMb {
    display: block !important;
  }
  .container1 .subject {
    padding: 0;
  }
  .container1 .subject .title {
    margin-top: 11px;
    margin-bottom: 14px;
  }
  .container1 .subject .videoCont {
    box-sizing: border-box;
    padding-left: 5px;
    padding-right: 5px;
    margin-bottom: 12px;
  }
  .container1 .subject .videoCont .nav {
    margin-bottom: 6px;
  }
  .container1 .subject .videoCont .nav .question_Nav {
    padding-left: 8px;
  }
  .container1 .subject .videoCont .nav .question_Nav .font {
    font-size: 14px;
  }
  .container1 .subject .videoCont .nav .panel_Nav {
    padding-left: 8px;
  }
  .container1 .subject .videoCont .nav .panel_Nav .font {
    font-size: 14px;
  }
  .container1 .subject .videoCont .nav .operation_Nav {
    padding-left: 8px;
  }
  .container1 .subject .videoCont .nav .operation_Nav .font {
    font-size: 14px;
  }
  .container1 .subject .videoCont .videoItem {
    width: 49.5%;
    margin-right: 1%;
  }
  .container1 .subject .videoCont .videoItem img {
    padding: 0;
  }
  .container1 .subject .videoCont .videoItem p {
    margin-top: 8px;
    margin-bottom: 13px;
    font-size: 14px;
  }
  .container1 .subject .videoCont .videoItem:nth-child(3n+3) {
    margin-right: 1%;
  }
  .container1 .subject .videoCont .videoItem:nth-child(2n) {
    margin-right: 0;
  }
  .container1 .subject img {
    width: 100%;
    display: block;
    box-sizing: border-box;
    padding: 0 5px;
  }
  .container1 .subject .btnCont {
    position: absolute;
    bottom: 2.43%;
    right: 3.26%;
  }
  .container1 .subject .btnCont .caozuo {
    display: block;
    width: 70%;
    margin-bottom: 8px;
    padding: 0;
  }
  .container1 .subject .btnCont .btn {
    display: block;
    width: 70%;
    padding: 0;
  }
  .container1 .popupDiv .iframeDiv {
    left: 5%;
    width: 90%;
  }
  .container1 .popupDiv .iframeDiv img {
    width: 30px;
    right: 0;
  }
  .isPc {
    display: none !important;
  }
}