.main {
  width: 1200px;
  margin: 0 auto;
}
header .header_top {
  height: 35px;
  background-color: #434343;
  color: #fff;
}
header .header_top .top_content {
  font-size: 12px;
  display: flex;
  justify-content: space-between;
  line-height: 35px;
}
header .header_top .top_content .tel {
  display: inline-block;
}
header .nav .nav_content {
  height: 87px;
  line-height: 87px;
  display: flex;
}
    header .nav .nav_content .logo {
        width: 423px;
        height: 87px;
        display:flex;
        align-items:center;
        margin-right: 40px;
    }
      
        header .nav .nav_content .nav_list {
            flex: 1;
            display: flex;
            justify-content: space-between;
            height: 87px;
            align-items: center;
        }
header .nav .nav_content .nav_list .nav_item {
  height: 100%;
  line-height: 87px;
  font-size: 16px;
  width: 71px;
  font-weight: 700;
  position: relative;
}
header .nav .nav_content .nav_list .nav_item span {
  display: inline-block;
  width: 100%;
  line-height: 40px;
  height: 40px;
  text-align: center;
}
header .nav .nav_content .nav_list .nav_item .blue {
  border-bottom: 1px solid #01388b;
  color: #01388b;
}
header .nav .nav_content .nav_list .nav_item .down_list {
  position: absolute;
  left: -30px;
  height: 137px;
  width: 135px;
  background-color: #01388b;
  line-height: normal;
  z-index:999;
}
header .nav .nav_content .nav_list .nav_item .down_list li {
  color: #fff;
  font-size: 16px;
  height: 35px;
  text-align: center;
  line-height: 35px;
}
header .nav .nav_content .nav_list .down_arrow1:hover::after {
  width: 71px;
  height: 8px;
  content: '';
  position: absolute;
  bottom: 16px;
  right: 0px;
  background-image: url(../images/首页/三角形1.png);
  background-repeat: no-repeat;
}