.mdlWait{
    display: none;
    position: fixed;
    z-index: 1000;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    background: rgba(255,255,255,.3)
    url("http://localhost:8000/img/Eclipse-1s-200px.gif")
    50% 50%
    no-repeat;
}

body.loading .mdlWait{
    overflow: hidden;
}
body.loading .mdlWait{
    display: block;
}