Media queries for landscape printing?

<style>
    @media print {
        @page {
            size: landscape; /*automatically set to Landscape only*/
        }
    }
</style>

If you want letting the user to choose between the two ways : portrait/Landscape, do :

 <style type="text/css" media="print">
        @page {
            /* portrait/Landscape */
            size: auto;
           /*adding some margins to let the title and the date to be displayed*/
            margin: 40px 10px 35px; 
        }
  </style>

Media Queries offer matching against the device's orientation:

@media print and (orientation: landscape) {
    /* landscape styles */
}

@media print and (orientation: portrait) {
    /* portrait styles */
}