.bg {

    animation:slide 10s ease-in-out infinite alternate;

    background-image: linear-gradient(-60deg, #d5d950 50%, #751212 50%);

    bottom:0;

    left:-50%;

    opacity:.2;

    position:fixed;

    right:-50%;

    top:0;

    z-index:-1;

}



.bg2 {

    animation-direction:alternate-reverse;

    animation-duration:10s;

}



.bg3 {

    animation-duration:10s;

}



.content {

    background-color:rgba(255,255,255,.8);

    border-radius:.25em;

    box-shadow:0 0 .25em rgba(0,0,0,.25);

    box-sizing:border-box;

    left:50%;

    padding:10vmin;

    position:fixed;

    text-align:center;

    top:50%;

    transform:translate(-50%, -50%);

}



@keyframes slide {

    0% {

        transform:translateX(-25%);

    }

    100% {

        transform:translateX(25%);

    }

}