body {
       background-color: #abd0bb;

#container
{
	position: relative;
        width: 100%;
        height: auto; 
	background: transparent;
}

#content-container
{
	float: left;
	width: 100%;
	background: transparent
}

#img.responsive
{
         max-width: 100%; 
         height: auto;
}

@media only screen and (max-width: 600px) {
        #img.responsive {
            background-image: url("image-small.png");
        }
    }
    @media only screen and (min-width: 601px) and (max-width: 900px) {
        #img.responsive {
            background-image: url("image-medium.png");
        }
    }
    @media only screen and (min-width: 901px)  {
        #img.responsive {
            background-image: url("image-large.png");