.omc-overlay-spinner {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    z-index: 30000000;
}
.omc-overlay-spinner .spinner {
    background: none;
    display: inline-block;
    float: none;
    height: auto;
    margin: auto;
    opacity: 1;
}