@media only screen and (max-width:767px) {
.header img {
    height: 30px;
}

.banner {
    height: calc(100vh - 80px);
    background:url(../img/banner_mobile.png) 75% 50% no-repeat;
    background-size:cover;
}

.served {
    height:100vh;
    background:url(../img/banner_second_mobile.png) 20% 50% no-repeat;
    background-size:cover;
}
}