function fish_dropMenu() 
{ 
    $("#top-nav ul ").css({display: "none"}); 

    $("#top-nav li").hover(function() { 
        $(this).find('ul:first').css({visibility: "visible", display: "none"}).slideDown(); 
        $(this).addClass("current");
    }, function() { 
        $(this).find('ul:first').css({visibility: "hidden"});
        $(this).removeClass("current");
    });
}

$(document).ready(function(){
    fish_dropMenu(); 
});