.android-go {
    background: url('button-android.png') no-repeat 0px 0px;
    width: 444px;
    height: 103px;
    display: inline-block;
    text-decoration: none!important;
}
.android-go:hover {
    background-position: 0px -103px;
}

@media screen and (max-width: 767px) {
    .android-go {
        float: none;
	    margin-left: -15px;
	    background-position-x: -5px;
	    background-size: 85%;
	    height: 80px;
    }
    .android-go:hover {
        background-position: 0px -89px;
    }
}