.img-box {
  width: 100%;
  height: 380px;
  background-image: url(../images/anli.png);
  -webkit-background-size: cover;
  background-size: cover;
  background-position-y: -80px;
}

.img-box .mark {
  width: 100%;
  height: 100%;
  /* background: rgba(0, 0, 0, 0.46); */
  background:none;
}

.img-box .main {
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.img-box h2,
.img-box h3 {
  padding-left: 65px;
  font-size: 46px;
  font-weight: 400;
  color: #ffffff;
  line-height: 80px;
  text-align: center;
}

.img-box h3 {
  font-size: 24px;
}

.demo-nav-list {
  display: flex;
  height: 72px;
  font-size: 15px;
  align-items: center;
  padding-left: 10px;
}

.demo-nav-list .dnl-item {
  margin-right: 50px;
  cursor: pointer;
}

.demo-nav-list .dnl-item:hover,
.demo-nav-list .dnl-item.active {
  color: #22c999;
}

.demo-list {
  padding-top: 20px;
  padding-bottom: 20px;
  background: #f1f1f5;
}

.demo-list .dl-item {
  padding: 0;
}

.demo-list .dl-item-box {
  margin: 15px 12px;
  box-shadow: -1px 6px 13px 0 rgba(110, 110, 110, 0.18);
}

.dl-item-box .dl-img-box {
  position: relative;
  overflow: hidden;
}

.dl-img-box .mark {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 100%;
  left: 0;
  background: rgba(256, 256, 256, 0.5);
  background: #ffffff;
  transition: top 0.3s ease-in-out;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  padding: 18px;
}

.dl-img-box .mark .qrcode-box {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: -20px;
}

.dl-img-box .mark .qrcode-box img {
  width: 130px;
}

.dl-img-box .mark .info-box {
  text-indent: 2em;
  color: #666666;
}

.dl-img-box:hover .mark {
  top: 0;
}

.dl-img-box .item-img {
  width: 100%;
  height: 260px;
  margin-bottom: -8px;
}

@media (max-width: 480px) {
  .img-box h2 {
    font-size: 20px;
    padding-left: 20px;
  }

  .img-box {
    height: 250px;
  }

  .about-title {
    font-size: 30px;
  }

  .about-title-sub {
    font-size: 26px;
  }

  .about-content {
    font-size: 18px;
  }
}