function getHeight() {
	var windowHeight = 0;
	if( typeof( window.innerWidth ) == 'number' ) {
		//Non-IE
		windowHeight = window.innerHeight;
	} else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
		//IE 6+ in 'standards compliant mode'
		windowHeight = document.documentElement.clientHeight;
	} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
		//IE 4 compatible
		windowHeight = document.body.clientHeight;
	}
	if ( windowHeight > 700 ) {
		$('main').className = 'big_resolution';
	} else {
		$('main').className = '';
	}
}