.video ul {
  list-style: none;
}
.video {
  background-color: #f7faff;
}
.video .header {
  position: relative;
  height: 484px;
  background-color: #97a8c2;
}

.video .header img {
  width: 100%;
  height: 484px;
}

.msg {
  position: absolute;
  top: 117px;
  left: 276px;
}
.msg .logo-box {
  display: flex;
  align-items: flex-end;
  font-weight: 500;
  font-size: 40px;
  color: #ffffff;
  line-height: 56px;
  margin-bottom: 21px;
}
.msg .logo-box .title {
  font-weight: 500;
  font-size: 40px;
  color: #ffffff;
  line-height: 38px;
}
.msg .logo-box img {
  width: 140px;
  height: 50px;
  margin-right: 9px;
}
.msg .desc {
  font-weight: 400;
  font-size: 26px;
  color: #ffffff;
  line-height: 42px;
  margin-bottom: 30px;
}
.msg .btn {
  display: flex;
  align-items: center;
  background-color: #fff;
  padding: 18px 31px;
  width: max-content;
  border-radius: 5px;
  font-weight: 600;
  font-size: 20px;
  color: #228fff;
  cursor: pointer;
}
.msg .btn img {
  width: 26px;
  height: 26px;
  margin-left: 10px;
}
.main {
  display: flex;
  width: 1200px;
  margin: 0 auto;
  padding-bottom: 30px;
  flex-direction: column;
}
.main .tab-nav {
  width: 100%;
  display: flex;
  justify-content: space-around;
  align-items: center;
  background: rgba(255, 255, 255);
  border-radius: 8px;
  padding: 33px 0;
  transform: translateY(-50%);
}
.main .tab-nav li {
  font-weight: 500;
  font-size: 22px;
  color: rgba(51, 51, 51, 0.8);
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
  position: relative;
}
.main .tab-nav li img {
  width: 35px;
  height: 8px;
  margin-top: 8px;
  display: none;
}
.main .tab-nav .active img {
  display: block;
  position: absolute;
  top: 100%;
  transform: translate(-50%, -60%);
  animation: icon-expand 0.3s ease-in-out forwards;
}
/* icon展开动画 */
@keyframes icon-expand {
  0% {
    transform: scale(0);
  }
  100% {
    transform: scale(1);
  }
}
.main .tab-nav .active {
  font-weight: 500;
  font-size: 22px;
  color: #333333;
}
.main .list {
  display: flex;
  flex-wrap: wrap;
  margin: 0 -11px;
}
.main .list .item {
  cursor: pointer;
  display: flex;
  flex-direction: column;
  width: 283px;
  height: 252px;
  margin-top: 24px;
  margin: 12px 11px;
  border-radius: 8px;
  overflow: hidden;
  background-color: #ffffff;
}
.line2 {
  word-break: break-all;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-box {
  position: relative;
}
.main .list .item:hover .icon {
  display: block;
  /* 从小到大 */
  animation: icon-expand 0.3s ease-in-out forwards;
  position: absolute;
  top: calc(50% - 24px);
  left: calc(50% - 24px);
  transform: translate(-50%, -50%);
  width: 48px;
  height: 48px;
}
.main .list .item .icon {
  display: none;
}
.main .list .item .thumb {
  width: 282.5px;
  height: 156px;
  background-color: #d8d8d8;
  object-fit: cover;
}
.main .list .item .content {
  padding: 24px 20px;
  font-weight: 500;
  font-size: 17px;
  color: #333333;
  line-height: 24px;
}
.page-age{
  align-items: center;
}