#conteneur{
 text-align:center;
 vertical-align:middle;
 height:100%;
 width:100%;
}
.accessibilite{
 position:absolute;
 left:-1000px;
}

#page_video{
 position:relative;
 width: 700px;
 height: 500px;
 background: transparent url(../images/fondvideo.jpg) no-repeat;
}

#cadre_video{
 position: absolute;
 left: 263px;
 top:105px;
}

#bt_retour_video{
 position: absolute;
 left: 615px;
 top:10px;
}