$(function() {
    //alert($(window).height());
    $('#clickmenu').click(function() {
        $('#x_menu').center();
        $('.bg').show();
        $('#x_menu').fadein();
    });
    $('#closebt').click(function() {
        $('#x_menu').hide();
        $('.bg').hide();
    });
    $('.bg').click(function() {
        $('#x_menu').hide();
        $('.bg').hide();
    });
    /*var val=$(window).height();
	var codeheight=$("#code").height();
    var topheight=(val-codeheight)/2;
	$('#code').css('top',topheight);*/
    jquery.fn.center = function(loaded) {
        var obj = this;
        body_width = parseint($(window).width());
        body_height = parseint($(window).height());
        block_width = parseint(obj.width());
        block_height = parseint(obj.height());

        left_position = parseint((body_width / 2) - (block_width / 2) + $(window).scrollleft());
        if (body_width < block_width) {
            left_position = 0 + $(window).scrollleft();
        };

        top_position = parseint((body_height / 2) - (block_height / 2) + $(window).scrolltop());
        if (body_height < block_height) {
            top_position = 0 + $(window).scrolltop();
        };

        if (!loaded) {

            obj.css({
                'position': 'absolute'
            });
            obj.css({
                'top': ($(window).height() - $('#x_menu').height()) * 0.5,
                'left': left_position
            });
            $(window).bind('resize', function() {
                obj.center(!loaded);
            });
            $(window).bind('scroll', function() {
                obj.center(!loaded);
            });

        } else {
            obj.stop();
            obj.css({
                'position': 'absolute'
            });
            obj.animate({
                'top': top_position
            }, 200, 'linear');
        }
    }

})