.device-overlay {
    position: fixed;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    background: rgba(0,0,0,0.4);
}

.device-overlay-container {
    display: table;
    position: fixed;
    left: 50%;
    top: 50%;
    width: 324px;
    height: 200px;
    margin-left: -162px;
    margin-top: -150px;
    background: #FFF;
}

.device-overlay-text {
    text-align: center;
    display: table-cell;
    vertical-align: middle;
}