#alerts {
    position: fixed;
    bottom: 1rem;
    right: 1rem;
    z-index: 4;
    transition: height .3s ease-in;
}

#alerts .alert {
    position: relative;
}

#alerts .alert .alert-close {
    position: absolute;
    top: 35%;
    right: 10px;
    color: #777;
    cursor: pointer;
}

#alerts .alert.showing {
    animation: alert-show 0.5s;
}

#alerts .alert.removing {
    animation: alert-remove 0.5s;
}

@keyframes alert-show {
    from {
        bottom: -100px;
    }
    to {
        bottom: 0;
    }
}

@keyframes alert-remove {
    from {
        right: 0;
    }
    to {
        right: -500px;
    }
}