.affiches1 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/1.png)}
.affiches1 a:hover{background:url(img/impressions/affiches/1_thumbs.png)}
.affiches2 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/2.png)}
.affiches2 a:hover{background:url(img/impressions/affiches/2_thumbs.png)}
.affiches3 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/3.png)}
.affiches3 a:hover{background:url(img/impressions/affiches/3_thumbs.png)}
.affiches4 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/4.png)}
.affiches4 a:hover{background:url(img/impressions/affiches/4_thumbs.png)}
.affiches5 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/5.png)}
.affiches5 a:hover{background:url(img/impressions/affiches/5_thumbs.png)}
.affiches6 a{float:left;width:140px;height:140px;background:url(img/impressions/affiches/6.png)}
.affiches6 a:hover{background:url(img/impressions/affiches/6_thumbs.png)}