.logo-big {
    background-image: url(../img/ballerina_logo_white_2.png);
    background-size: contain;
    background-repeat: no-repeat;
    width: 40vh;
    height: 40vh;
    overflow: hidden;
    text-indent: -10000px;
    margin-bottom: 2vh;
}

h1.sitename, h3.sitename {
    background-image: url(../img/logo_dx_white.png);
    background-size: contain;
    background-repeat: no-repeat;
    height: 60px;
    width: 160px;
    overflow: hidden;
    text-indent: -10000px;
}

.bt-item {
    background-repeat: no-repeat;
    background-size: cover;
    position: absolute;
    top: 0px;
    left: 0px;
    bottom: 0px;
    right: 0px;
    opacity: 0.2;
}
.bt-scuola {
    background-image: url(../img/scuola_danza.jpg);
}
.bt-insegnanti {
    background-image: url(../img/insegnante_danza.jpg);
}
.bt-compagnie {
    background-image: url(../img/compagnia_teatrale_2.jpg);
}
.bt-teatri {
    background-image: url(../img/teatro.jpg);
}
.bt-collaboratori {
    background-image: url(../img/collaboratori.jpg);
}
.bt-mecenati {
    background-image: url(../img/mecenate.jpg);
}
.bt-brand {
    background-image: url(../img/brand.jpg);
}