JS: Smooth scroll from links with hashed href with fixed header

JS: Smooth Scroll Hashed Links

// Smooth scrolling of hashed links (#id)
$('a[href*=#]:not([href=#])').click(function() {
    if (location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') 
        || location.hostname == this.hostname) {

        var target = $(this.hash);
        target = target.length ? target : $('[name=' + this.hash.slice(1) +']');
           if (target.length) {
             $('html,body').animate({
                 scrollTop: target.offset().top - 20
            }, 600);
            return false;
        }
    }
});