#sound {
    background-image: url(../images/sound_1920.jpg);
    height: 776px;
    background-position: center -150px;
}

@media screen and (max-width: 1366px) {
    #sound {
        background-image: url(../images/sound_1366.jpg);
        height: 650px;
    	background-position: center -100px;
    }
}

@media screen and (max-width: 960px) {
    #sound {
        background-image: url(../images/sound_960.jpg);
        height: 500px;
        background-position: center bottom;
    }
}

@media screen and (max-width: 640px) {
    #sound {
        background-image: url(../images/sound_640.jpg);
        height: 622px;
        background-position: center 140px;
    }
}