header.masthead {
    background-image: -webkit-linear-gradient(rgba(0, 0, 0, 0.52), rgba(0, 0, 0, 0.52)), url(/static/img/wellness_dog.jpg);
    background-position: center top 25%;
}

/*@media (min-width: 768px) {*/
/*    header.masthead {*/
/*    }*/
/*}*/