.navbar.navbar-default .navbar-brand img {
    width: 230px !important;
}

@media only screen and (min-width: 768px)  {
    .navbar.navbar-default .navbar-brand img {
        width: 350px !important;
    }
}

@media only screen and (min-width: 920px)  {
    .navbar.navbar-default .navbar-brand img {
        width: 230px !important;
    }
}

@media only screen and (min-width: 1200px)  {
    .navbar.navbar-default .navbar-brand img {
        width: 350px !important;
    }
}