:root {
    --circle-pos-x:50vw;
    --circle-pos-y:50vh;
}

@keyframes backgroundCircle {
    0% {
        opacity: 0;
        transform: scale(0);
        top: 50vh;
        left: 50vw;
    }

    60% {
        left: var(--circle-pos-x);
        top: var(--circle-pos-y);
        transform: scale(1);
        opacity: 1;

    }
    100% {
        transform: scale(0);

        opacity: 0;
        top: 50vh;
        left: 50vw;
    }
}

.background {
    position: relative;
}
.background-circle {
    --circle-pos-x:50vw;
    --circle-pos-y:50vh;
    animation: backgroundCircle 6s;
    content:"";
    position: absolute;
    background: var(--color-secondary);
    width: 9px;
    height: 9px;
    border-radius: 50%;
}