body {
    background-attachment: fixed;
    background-image:url(../images/bg-repeat-x-noir.jpg);
    background-repeat:repeat-x;
    width:auto; /* on rétablit l'alignement normal du texte */  
    margin:0px;
}

.colonne_gauche {
float:left;
width:100%;
height:auto;
background-image:url(../images/colonne_gauche.jpg);
background-position:top;
background-repeat:no-repeat;
}


