Set screen orientation to the body tag

setScreenOrientation

function _getScreenOrientation() { 
	
	/* 
		returns screen orientation(landscape|portrait) and 
		set the attribute on the body "data-landscape[true|false]" 
	*/
	
	if ( window.orientation == ( -90 || 180 ) ) {
		document.body.setAttribute('data-landscape', 'true');
		return 'landscape';
	}
	else {
		document.body.setAttribute('data-landscape', 'false');
		return 'portrait';
	}
}