#bg { position: fixed; top: 0; left: 0; z-index: -1 }
.bgwidth { width: 100%; }
.bgheight { height: 100%; }


.element {
    display: inline-block;
    width: 200px;
    height: 200px;
    background: #f44336;
}

@media (min-width: 400px) {
    .element {
        background: url("../img/phone_bg.jpg");
    }
}

@media (min-width: 500px) {
    .element {
        background: #888888;
    }
}

@media (min-width: 600px) {
    .element {
        background: #222222;
    }
}



.footer {
    position: absolute;
    bottom: 0;
    width: 100%;
    height: 5%;
    background-color: rgba(0, 0, 0, 0.4);
    align-content: center;
}