body {
  background-image: url(../assets/img/bg底纹@2x.png);
    background-position: bottom;
    background-repeat: no-repeat;
    background-size: 100%;
    background-attachment: fixed;
}
/* 中间主题 */
.main {
  width: 100%;
  padding: 70px 0 40px 0;
  /* background: #f8f8f8; */
  min-height: calc(90vh - 86px);
}
.main-back a{
  font-size: 20px;  
}
.main-center {
  width: 1500px;
  margin: 0 auto;
  background-color: #fff;
}
.main-center-content {
  width: 67%;
  margin: 0 auto;
  padding: 50px 0 30px 0;
}
.main-content-title {
  text-align: center;
  font-size: 28px;
  font-weight: 500;
  color: #333333;
}
.main-content-subhead {
  text-align: center;
  margin: 22px 0 30px 0;
  font-size: 18px;
  color: #808080;
}
.main-content-subhead span {
  margin: 0px 20px;
}
/* .main-content-article p {
  font-size: 20px;
  font-weight: 500;
  text-indent: 2em;
  line-height: 35px;
  color: #333333;
  padding-bottom: 50px;
} */


.backtop {
  background-color: #9a9ca3;
  width: 50px;
  height: 50px;
  position: fixed;
  top: 787px;
  right: 150px;
  cursor: pointer;
}


@media screen and (max-width: 1610px) {
  .main-center {
    width: 1200px;
  }
}

@media screen and (max-width: 1330px) {
  .main-center {
    width: 900px;
  }
}

@media screen and (max-width: 1030px) {
  .main-center {
    width: 700px;
  }
}

@media screen and (max-width: 830px) {
  .main-center {
    width: 600px;
  }
}