.popup {
    position: fixed;
    top: 10px;
    left: 10px;
    transition: top 2s ease 0s;
}

.popup-in {
    animation: anim-popup-in 1s;
}

.popup-out {
    animation: anim-popup-out 1s;
}

@keyframes anim-popup-in {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes anim-popup-out {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}