jQuery(function($) {
	center_main_vertically();
});

$(window).resize(function(){
	center_main_vertically();
});

function center_main_vertically() {
	var mainTop = $(window).height() / 2 - $('#main').height() / 2;
	if ( mainTop < 0 )
	{
		mainTop = 0;
	}
	else
	{
		mainTop = Math.ceil( mainTop );
	}
	$('#main').css('margin-top', mainTop + 'px');
}