.topBg{
    max-width: 1920px;
    max-height: 588px;
    min-height: 500px;
    margin: 0 auto;
    background: url(https://imagefile-1325623149.cos.ap-beijing.myqcloud.com/customeServer/website/activity/activity_bg.png) no-repeat;
    background-size: cover;
}

.is_kong{
    margin: 160px auto;
    text-align: center;
    font-size: 28px;
    color: #525558;
}
.img_bg{
    width: 434px;
    height: 350px;
    margin-bottom: 20px;
    background: url(https://imagefile-1325623149.cos.ap-beijing.myqcloud.com/customeServer/website/activity/activity_kong.png) no-repeat;
}
.title{
    /*font-size: 30px;*/
    font-size: 24px;
    color: #232323;
    font-weight: 600;
    line-height: 100px;
}
p {
    font-size: 20px;
    color: #525558;
    line-height: 40px;
    text-indent: 4ch; /* 使用字符单位 */
}