body {
    position: relative;
}
div#message {
    text-align: center;
    margin: -50px 0 0 -50%;
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100%;
    height: 100px;
}

div#message > span {
    color: #ffffff;
    text-align: center;
    font-size: 6vmin;
    height: 100px;
    /*line-height: 100px;*/
    margin-bottom: 20px;
}

div#cover_image {
    width: 100%;
    height: 100%;
    background-color: #000000;
    z-index: 1;
    display: inline-block;
    vertical-align: middle;
    background-repeat: no-repeat;
    background-position: 50% 50%;
    background-size: contain;
    cursor: pointer;
    margin: 0px;
    padding: 0px;
    position: absolute;
    top: 0px;
    right: 0px;
    bottom: 0px;
    left: 0px;
    visibility: visible;
}