$(document).ready(function(){
    $('ul.mainmenu').addClass('ready');
    
    //nav_container.height(nav_closed_height);
    $('ul.mainmenu > li').each(function() {
        var nav_container = $(this).find('ul.submenu');
        var nav_open_height = nav_container.height();
        var nav_closed_height = 0;
        $(this).hover(
            function() {
                $(this).addClass('hover');
                nav_container.animate({
                      'height': nav_open_height
                    }, 
                    {
                        duration: 'slow',
                        easing: 'backEaseOut',
                        queue: false
                });
            },
            function() {
                $(this).removeClass('hover');
                nav_container.animate({
                        'height': nav_closed_height
                    }, 
                    {
                        duration: 'slow',
                        easing: 'backEaseIn',
                        queue: false
                });
            }
        );
        nav_container.height(nav_closed_height);
    });
    
});