#global-app{
    overflow: hidden;
}
.activity-main{
    width: 100%;
    overflow: hidden;
    position: relative;
    height: 3278px;
}
.activity-bg{
    width: 1920px;
    height: 3278px;
    margin: auto;
    background: url(https://qiniu.htknow.com/18164_adf032c8d1f7feb7c55309643b6d0c04.jpg) no-repeat center center;
    background-size: cover;
    position: absolute;
    left: 50%;
    top: 0;
    transform: translateX(-50%);
}
.avtivity-history{
    width: 100%;
    height: 137px;
    background: url(https://qiniu.htknow.com/18164_dc05d4077914e3d46d6d89fbc76cbeec.png) no-repeat center center;
    background-size: cover;
    position: absolute;
    bottom: 0;
}