#wrapper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255,255,255,.6);
    z-index: 1001;
}

#popup {
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, .4);
    position: absolute;
    margin-left: auto;
    margin-right: auto;
    left: 0;
    right: 0;
}