.sutong-about {
  padding: 40px 0 ;
}

.sutong-about h3 {
  font-size: 40px;
  font-weight: 700;
  line-height: 1;
  position: relative;
  z-index: 20;
  text-align: center;
}

.sutong-about h3::before {
  display: block;
  content: attr(data-txt);
  white-space: nowrap;
  color: #fff;
  position: absolute;
  left: 0;
  top: -38px;
  font-size: 98px;
  line-height: 1;
  z-index: -1;
  text-shadow: rgba(210, 217, 221, .75) 1px 0 0, rgba(210, 217, 221, .75) 0 1px 0, rgba(210, 217, 221, .75) -1px 0 0, rgba(210, 217, 221, .75) 0 -1px 0
  display: none;
  
}

.sutong-about h3::after {
  display: block;
  content: '';
  width: 80px;
  height: 2px;
  background: var(--color-primary);
  margin: 10px auto 0 0;
  display: none;
}

.sutong-about .txt {
  position: relative;
  margin: 40px 0 0;
  line-height: 36px;
  font-size: 17px;
}

.sutong-about .txt *+* {
  margin-top: 60px
}

.sutong-about .txt img {
  width: 100%;
}

.sutong-about .txt::after {
  content: "";
  position: absolute;
  right: 0;
  top: 16%;
  bottom: 16%;
  width: 20%;
  background-color: color-mix(in srgb, var(--color-primary) 30%, transparent);
  z-index: -1;
  display: none;
}

.sutong-about ul {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap
}

.sutong-about ul li {
  width: calc(50% - 30px);
  padding: 80px 0 54px;
  border-bottom: 2px solid #ddd;
  display: flex;
  flex: 0 0 25%;
  width: 25%;
}

.sutong-about ul li .ico {
  width: 124px;
  text-align: center;
  display: none;
}

.sutong-about ul li .t {
  flex: 1;
  margin-left: 17px
}

.sutong-about ul li .t h5 {
  font-size: 20px;
  font-weight: 700;
  line-height: 1
}

.sutong-about ul li .t p {
  font-size: 15px;
  line-height: 29px;
  margin: 20px 0 0
}

@media screen and (max-width: 1441px) {

  .sutong-about h3::before {
    font-size: 90px
  }

  .sutong-about h3 {
    font-size: 38px
  }

  .sutong-about {
    padding: 110px 0 40px
  }
}

@media screen and (max-width: 1367px) {

  .sutong-about h3::before {
    font-size: 80px
  }

  .sutong-about h3 {
    font-size: 36px
  }

  .sutong-about {
    padding: 90px 0 40px
  }

  .sutong-about .txt {
    margin: 30px 0 0;
    line-height: 32px
  }

  .sutong-about .txt *+* {
    margin-top: 30px
  }

  .sutong-about ul li {
    padding: 70px 0 50px;
    flex: 0 0 100%;
    max-width: 100%;
  }
}

@media screen and (max-width: 1281px) {

  .sutong-about h3::before {
    font-size: 70px
  }

  .sutong-about h3 {
    font-size: 34px
  }
}

@media screen and (max-width: 1171px) {

  .sutong-about h3::before {
    font-size: 60px
  }

  .sutong-about h3 {
    font-size: 32px
  }
}

@media screen and (max-width: 992px) {

  .sutong-about ul li {
    width: 100%;
    padding: 40px 0;
    flex: 0 0 50%;
    max-width: 50%;
  }
}

@media screen and (max-width: 768px) {
  .sutong-about h3::before {
    font-size: 50px
  }

  .sutong-about h3 {
    font-size: 30px
  }

  .sutong-about {
    padding: 40px 0 0
  }

  .sutong-about h3 {
    text-align: center
  }

  .sutong-about h3::before {
    left: 0;
    right: 0;
    text-align: center;
    top: -20px
  }

  .sutong-about h3::after {
    margin: 10px auto 0
  }

  .sutong-about .txt {
    margin: 20px 0 0;
    line-height: 26px
  }

  .sutong-about .txt *+* {
    margin-top: 20px
  }

  .sutong-about ul li {
    padding: 30px 0;
    flex: 0 0 100%;
    max-width: 100%;
  }

  .sutong-about ul li .t p {
    line-height: 24px;
    margin: 15px 0 0;
  }
}

@media screen and (max-width: 576px) {

  .sutong-about h3::before {
    font-size: 40px
  }
}

@media screen and (max-width: 480px) {

  .sutong-about .pic {
    width: 320px;
    height: 192px;
    background-size: 320px 192px;
    padding: 14px 0 0 22px
  }

  .sutong-about .pic .v {
    width: 277px
  }
}