.exampleA {
    background-image: url("../img/big/big_1.jpg");
}
.exampleB {
    background-image: url("../img/big/pannello_eva.gif");
}
.exampleC {
    background-image: url("../img/big/pannello_kappa.gif");
}
.exampleD {
    background-image: url("../img/big/pannello_qs.gif");
}
.exampleE {
    background-image: url("../img/big/pannello_tonosutono.gif");
}
.exampleF {
    background-image: url("../img/big/pannello_lds.gif");
}