#body {
    overflow: hidden;
    opacity: .1;
}
#loading {
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 99999999999;
    width: 100vw;
    height: 100vh;
    background-image: url("loading.gif");
    background-size: 150px 150px;
    background-repeat: no-repeat;
    background-position: center;
    background-color: #fff;
}