body{
    margin: 0;
    padding: 0;
    background: #F5F7FA;
    color: #434A54;
    font-size: 85%;
    font-family: "微软雅黑";
}
.title{
    line-height: 2.1em;
    text-align: center;
    font-weight: bold;
    font-size: 1.4em;
}
.qr_code{
    text-align: center;
    background: white;
}
.qr_code img{
    padding-top: 3em;
    padding-bottom: 0.7em;
    width: 15em;
    display:block;
    margin: auto;
}
.qr_code span{
    padding-bottom: 3em;
    display: block;
    font-weight: 600;
    letter-spacing: 0em;
    font-size: 1.2em;
}