scroll animate

$('a[href^="#"]').on('click', function(e){
        e.preventDefault();

        var
          $this = $(this),
          target = $this.attr('href'),
          strip = target.slice(1),
          anchor = $("[id='"+ strip +"']");

        $('html, body').animate({
                scrollTop: anchor.offset().top
        }, 2000);
 });