footer{
    background-image: url(http://localhost:8000/img/footer.jpg);
    background-size:cover;
    background-attachment: fixed;
}
#foot {
    color:white;
}
@media only screen and (max-width: 767px){
    #foot {
        width:100%; 
    }
}
@media only screen and (min-width:768px){
    #foot {
        width:25%;
    }
}