body{padding: 0;margin: 0;}

#imagem{background-image:url('tela2.jpg');width:100%;height:100%;background-size: cover;border:0;margin:0;background-position: center center;}
			
@media screen and (max-width: 480px) {
				
#imagem{background-image:url('mobile.jpg');width:100%;height:700px;background-size: cover;border:0;margin:0;background-position:top;}
				
}