* {
    padding: 0;
    margin: 0;
}

body {
    font-family: "Helvetica Neue", Helvetica, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, sans-serif;
    width: 375px;
    height: 1900px;
    overflow: hidden;
    background-image: linear-gradient(to bottom left, #F56C6C, #f5de2a);
}

html, body {
    overflow: hidden;
}

.first-b {
    width: 375px;
}

.first-qrcode {
    width: 220px;
    height: 220px;
    margin: 120px auto 0;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 12px 0 rgba(0, 0, 0, .3);
}

.first-qrcode img {
    width: 200px;
    height: 200px;
    margin: 10px 10px;
}

.first-txt {
    position: fixed;
    bottom: 160px;
    width: 375px;
    height: 40px;
    text-align: center;
    color: #fff;
    font-size: 14px;
}