[ealexseen]

Попробуй так

$(document).ready(function(){
        $('a[href^="#"]').on('click.smoothscroll',function (e) {
            var self = $(this),
                target = this.hash,
                $target = $(target);

            $('html, body').stop().animate({
                'scrollTop': $target.offset().top
            }, 900, 'swing', function () {
                window.location.hash = target;
                self.addClass(self.text());
            });

            return false;
        });
    });