Consulta de medios con diferentes CSS
<!-- Movil -->
<link href="movil.css" rel="stylesheet" type="text/css" media="only screen and (max-width:480px)">
<!-- Tablet -->
<link href="tablet.css" rel="stylesheet" type="text/css" media="only screen and (min-width:481px) and (max-width:768px)">
<!-- Monitor -->
<link href="monitor.css" rel="stylesheet" type="text/css" media="only screen and (min-width:769px)">