html {
    min-height: 100%;
    background-image: url("../images/bg.jpg");
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center center;
 }

body {
    padding: 0;
    margin: 0;
}

#devils_stone {
    background: url("../images/devils_stone.png") no-repeat;
    width: 495px;
    height: 134px;
    margin-left: auto;
    margin-right: auto;
    margin-top: 24px;
}

iframe {
    position: fixed;
    top: 534px;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.4), 0 6px 20px 0 rgba(0, 0, 0, 0.4); 
}