#content-container:after{

• content: "";
• position: absolute;
• top:0;
• left: 0;
• width: 100%;
• height: 100%;
• background-image: url(https://eoimages.gsfc.nasa.gov/images/imagerecords/80000/80435/kevir_tm5_2011288_lrg.jpg);
• background-size: cover;

}

#gb_70 { 
    background-image: url(
https://s1.qwant.com/thumbr/474x474/2/a/7408fe782e29df17ceba3568c489643f408bd11cc2aa6d83c8bf8848b8d4e2/th.jpg?u=https%3A%2F%2Ftse.mm.bing.net%2Fth%3Fid%3DOIP.RTfJHDWENQ5dA3UxSH_DBwHaHa%26pid%3DApi&q=0&b=1&p=0&a=0);
}

canvas {
    opacity: 0;
}