body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("../wallpaper.svg");
    background-repeat: no-repeat;
    background-size: cover;
    z-index: -1;
    opacity: 0;
    animation: fadeInOut 6.9s ease-in-out infinite;
}

@keyframes fadeInOut {
    0% { opacity: 11%; }
    22% { opacity: 42%; }
    88% { opacity: 42%; }
    100% { opacity: 11%; }
}