.banner a {
  background: -webkit-gradient(linear, left top, right top, color-stop(33.33%, #ffffff), color-stop(66.66%, #4270d5), to(#5c57c7));
  background: linear-gradient(to right, #ffffff 33.33%, #4270d5 66.66%, #5c57c7);
  background-size: 300% 100%;
  background-clip: text;
  -webkit-background-clip: text;
  color: transparent !important;
  background-position: 0% 0;
  -webkit-transition: background-position 0.5s ease;
  transition: background-position 0.5s ease;
}
.banner a:hover {
  background-position: 100% 0;
}

.banner {
  position: relative;
  z-index: 2;
  color: #fff;
  height: 100vh;
  overflow: hidden;
  mask-image: linear-gradient(
        to bottom,                    /* 渐变方向：从左到右 */
        transparent,                 /* 最左边：完全透明 */
        black ,     /* 从 --mask-width 位置开始：完全不透明（黑色） 不需要变量可以删除*/
        black , /* 直到 --right-mask-width 位置：保持不透明 不需要变量可以删除*/
        transparent                  /* 最右边：完全透明 */
    );
}
.banner:after{
    content:'';
    display: block;
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    background: rgba(0,0,0,0.2);
}
.banner img, .banner video {
  width: 100%;
  height: 100%;
  -o-object-fit: cover;
     object-fit: cover;
}
.banner .pc {
  display: none;
}
.banner .txt {
  position: absolute;
  z-index: 3;
  top: 50%;
  left: 50%;
  -webkit-transform: translate(-50%, -50%);
      -ms-transform: translate(-50%, -50%);
          transform: translate(-50%, -50%);
}
.banner .txt > div {
  width: 620px;
}
.banner .tit {
  font-weight: bold;
  line-height: 1.142;
}
.banner .sub {
  margin-top: 10px;
}
.banner .des {
  margin-top: 30px;
}
.banner .bread {
  position: absolute;
  z-index: 3;
  top: 102px;
  left: 50%;
  -webkit-transform: translateX(-50%);
      -ms-transform: translateX(-50%);
          transform: translateX(-50%);
  color: #fff;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
}
.banner .bread svg {
  margin-right: 16px;
}
.banner .bread span {
  margin: 0 10px;
}
.banner .phone {
  display: none;
}

@media screen and (max-width: 1700px) {
  .banner .bread {
    top: 92px;
  }
  .banner .des {
    margin-top: 15px;
  }
}
@media screen and (max-width: 1200px) {
  .banner .bread {
    top: 76px;
  }
}
@media screen and (max-width: 768px) {
  .banner {
    margin-top: 60px;
    height: auto;
  }
  .banner .bread {
    display: none;
  }
  .banner video {
    display: none;
  }
  .banner .des {
    display: none;
    margin-top: 10px;
  }
  .banner .phone {
    display: block;
  }
  .banner .pc {
    display: none;
  }
  .banner .txt > div {
    width: 100%;
  }
}