#content{
  padding-bottom: 180px;
  background: url('../imgs/about_bg.jpg') no-repeat center top/1920px;
}


#content::after{
  content: '';
  position: absolute;
  z-index: -1;
  left: -5px;
  top: -2px;
  width: 0%;
  height: 0%;
  border: 0px solid #fff;
}

.sec{
  padding-top: 180px;
  height: 330px;
}

.sec .cover img{
  width: 100%;
  height: 100%;
}

.sec .cover::after{
  content: '';
  position: absolute;
  z-index: -1;
  left: -5px;
  top: -2px;
  width: 100%;
  height: 100%;
  border: 3px solid #ff6537;
}

.sec1 .cover{
  display: block;
  width: 311px;
  height: 280px;
  margin-left: 140px;
}

.sec2 .cover{
  display: block;
  width: 303px;
  height: 280px;
}

.sec3 .cover{
  display: block;
  width: 309px;
  height: 280px;
  margin-left: 235px;
}

.sec .des .title{
  font-size: 20px;
  color: #666;
}

.sec .des .row{
  font-size: 14px;
  color: #7f7f7f;
  line-height: 1.8;
}

.sec1 .des{
  width: 600px;
  margin: 40px 25px 0;
}

.sec2 .des{
  width: 600px;
  margin: 40px 25px 0 85px;
}

.sec3 .des{
  width: 370px;
  margin: 20px 33px 0;
}