h1 {
    color: red;
}

.zesralessie {
    position: fixed;
    top: 50%;
    left: 50%;
    translate: -50% -50%;
    width: 100vw;
    opacity: 0;
    animation: zesralessieanim 8s ease forwards;
}

@keyframes zesralessieanim {
    0% {
        opacity: 0;
        scale: 1 0.8;
    }
    47% {
        opacity: 1;
        scale: 1 1;
    }
    53% {
        opacity: 1;
        scale: 1 1;
    }
    100% {
        opacity: 0;
        scale: 1 1;
    }
}