.header {
    min-height:300px;
    background-color:transparent;
    margin-bottom:20px;
}
img.image1 {
    height: auto;
    margin-right:auto;
}
@media only screen and (min-width : 768px) {
    .header {
        min-height: 159px;
    }
}
@media only screen and (min-width : 1024px) {
    img.image1 {
        height: 250px;
        display:block;
        margin-left:auto;
    }
    .header {
        min-height: 159px;
    }
}