div#SpinnerContainer {
    position: fixed;
    display: none;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    /*background-color: #fff;*/
    /*opacity: 0.4;*/
    background-color: rgba(0, 0, 0, 0.5);
    /*filter: alpha(opacity=40);*/ /* For IE8 and earlier */
    z-index: 1000; /* Important to set this */
}

div#Spinner {
    position: fixed;
    display: none;
    width: 50px;
    height: 50px;
    top: 48%;
    left: 48%;
    z-index: 1001;
    overflow: auto;
}