.loading-modal {
    display: none;
    position: fixed;
    z-index: 1000;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    background: rgba(56, 69, 86, 0.8) url('loading.gif') 50% 50% no-repeat;
}
/* When the body has the loading class, we turn
        the scrollbar off with overflow:hidden */
body.loading {
    overflow: hidden;
}

    body.loading .loading-modal {
        display: block;
    }