.viewer-backdrop {
    background-color: rgba(0,0,0,.9);
}
.ctn2 {
  position: relative;
  overflow: hidden;
}
.ctn2 ul {
  display: flex;
  flex-wrap: wrap;
}
.ctn2 ul li {
  width: 32%;
  margin-top: 30px;
  position: relative;
}
.ctn2 ul li .tu {
  position: relative;
  overflow: hidden;
}
.ctn2 ul li .tu:before {
  content: '';
  display: block;
  padding-top: calc(614 / 460 * 100%);
}
.ctn2 ul li .tu:after {
  content: '';
  width: 100%;
  height: 100%;
  position: absolute;
  left: 0;
  top: 0;
  background: url(/static/cn/img/case/mask.png) no-repeat;
  background-size: cover;
}
.ctn2 ul li .tu img {
  position: absolute;
  width: 100%;
  height: 100%;
  object-fit: cover;
  left: 0;
  top: 0;
  transition: all 0.5s;
  -webkit-transition: all 0.5s;
  -moz-transition: all 0.5s;
  -ms-transition: all 0.5s;
}
.ctn2 ul li .logos {
  position: absolute;
  top: 30px;
  left: 40px;
}
.ctn2 ul li .logos img {
  max-height: 100px;
}
.ctn2 ul li h2 {
  position: absolute;
  width: 100%;
  left: 0;
  bottom: 0;
  padding: 30px 40px;
  color: #fff;
}
.ctn2 ul li .tu-list{
    display: none;
}
.ctn2 ul li:not(:nth-child(3n)) {
  margin-right: 2%;
}
.ctn2 ul li:hover .tu img {
  transform: scale(1.05);
  -webkit-transform: scale(1.05);
  -moz-transform: scale(1.05);
  -ms-transform: scale(1.05);
}
@media screen and (max-width: 1440px) {
  .ctn2 ul li {
    margin-top: 20px;
  }
  .ctn2 ul li .logos {
    top: 20px;
    left: 30px;
  }
  .ctn2 ul li .logos img {
    max-height: 80px;
  }
  .ctn2 ul li h2 {
    padding: 20px 30px;
  }
}
@media screen and (max-width: 1200px) {
  .ctn2 ul li .logos {
    left: 20px;
  }
  .ctn2 ul li .logos img {
    max-height: 70px;
  }
  .ctn2 ul li h2 {
    padding: 14px 20px;
  }
}
@media screen and (max-width: 768px) {
  .ctn2 {
    padding-top: 5vw;
  }
  .ctn2 ul li {
    width: 100%;
    margin-top: 20px;
  }
  .ctn2 ul li .logos {
    top: 30px;
  }
  .ctn2 ul li:not(:nth-child(3n)) {
    margin-right: 0;
  }
}