.bszn_header{
    background: url(../images/beijing.png) top center no-repeat;
}

.bszn_container{
    width: 1240px;
    margin: 0 auto;
}

.header_top{
    display: flex;
    justify-content: right;
    padding: 10px 0 15px;
}

.header_top ul{
    display: flex;
    justify-content: flex-start;
}

.header_top ul li{
    line-height: 15px;
    padding: 0 8px;
    border-right: 1px solid #333333;
}

.header_top ul li#userlogin{
    border-right: none;
}

.header_top ul li,
.header_top ul li a{
    font-size: 14px;
    color: #333333;
}

.header_center,
.center_left,
.center_right,
.district{
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.hzs_img{
    margin-right: 60px;
}

.zwfw_sousuo{
    margin-right: 62px;
}

.zwfw_sousuo input{
    width: 185px;
    height: 32px;
    background: #FFFFFF;
    outline: none;
    border: none;
    padding-left: 9px;
}

.zwfw_sousuo a{
    width: 48px;
    height: 32px;
    line-height: 32px;
    text-align: center;
    background: #245399;
    font-size: 14px;
    color: #FFFFFF;
}

.district span{
    font-size: 16px;
    color: #245399;
    margin-right: 11px;
}

.district select{
    width: 52px;
    height: 24px;
    padding: 0 7px;
    background: #FFFFFF;
    outline: none;
    border: none;
    appearance: none; 
    background-image: url(../images/qiehunsa.png);
    background-repeat: no-repeat;
    background-position-y: center;
    background-position-x: 35px;
    color: #666666;
    font-size: 12px;
}

.header_nav{
    margin-top: 36px;
}

.header_nav ul{
    width: 76%;
    display: flex;
    justify-content: space-between;
}

.header_nav ul li{
    padding-bottom: 14px;
}

.header_nav ul li:hover,
.header_nav ul li.active{
    padding-bottom: 10px;
    border-bottom: 4px solid #245399;
}

.header_nav ul li a{
    font-weight: bold;
    font-size: 16px;
    color: #343434;
}

@media screen and (max-width:768px) {
    .bszn_header{
        padding: 0 10px;
        background-size: cover;
    }
    .bszn_container,
    .center_left,
    .center_left img,
    .center_right,
    .header_nav ul{
        width: 100%;
    }
    .header_center, 
    .center_left, 
    .center_right, 
    .district,
    .header_nav ul{
        flex-wrap: wrap;
    }
    .hzs_img,
    .zwfw_sousuo,
    .district span{
        margin-right: 0;
    }
    .center_left a{
        width: 47%;
    }
    .center_right{
        margin-top: 20px;
    }
    .zwfw_sousuo{
        width: 50%;
    }
    .zwfw_sousuo input{
        width: 72%;
    }
    .district{
        width: 43%;
    }
    .header_nav{
        margin-top: 25px;
    }
    .header_nav ul li{
        margin-right: 10px;
    }
}