var orientation = 0;
   
function updateOrientation() {
	orientation = window.orientation;
  switch(orientation) {
    case 0:
    case 180:
      $("body").removeClass("landscape");
      break; 
       
    case 90: // landscapeLeft
    case -90: //landscapeRight
			$("body").removeClass().addClass("landscape");
    	break;
  }
}

window.onorientationchange = function() {
  orientation = updateOrientation();
}