header {
    max-width: 90%;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
    overflow: hidden;
}

.row {
    display: flex;
    overflow: hidden;
}

.cell {
    
}
.imagegroup {
    display: flex;
    width: 100%;
}

.imagegroup {
    animation: travel 20s ease-in-out infinite;
}

@keyframes travel {
    0%, 100% {
        transform: translate3d(0,0,0);
    }
    25%, 50% {
        transform: translate3d(-100%,0,0);
    }
}

.imagegroup img {
    flex-shrink: 0;
    object-fit: cover;
}