html, body {
    margin: 0;
    padding: 0;
    background-position: center top;
    background-repeat: no-repeat;
}

body {
    width: 1000px;
    margin: 0 auto;
    position: relative;
    background-image: url(habillage.jpg);
}

iframe,#mask {
    width: 970px;
    height: 270px;
    display: block;
    position: absolute;
    top: 129px;
    left: 14px;
}
#mask{
    height: 280px;
    background-color: white;
}