Smooth scroll on affixed menu

by panchroma

HTML

<link rel="stylesheet" href="http://twitter.github.com/bootstrap/assets/css/bootstrap.css">
<div id="nav-wrapper">
<div id="nav" class="navbar navbar-inverse affix-top" data-spy="affix" data-offset-top="675">
  <div class="navbar-inner" data-spy="affix-top">
    <div class="container">

      <!-- .btn-navbar is used as the toggle for collapsed navbar content -->
      <a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </a>

      <!-- Everything you want hidden at 940px or less, place within here -->
      <div class="nav-collapse collapse">
        <ul class="nav">
            <li><a href="#home">Home</a></li>
            <li><a href="#service-top">Services</a></li>
            <li><a href="#contact-arrow">Contact</a></li>
        </ul><!--/.nav-->
      </div><!--/.nav-collapse collapse pull-right-->
    </div><!--/.container-->
  </div><!--/.navbar-inner-->
</div><!--/#nav /.navbar navbar-inverse-->
</div><!--/#nav-wrapper-->

<div id="home">
    <h1> Home </h1>
<!-- START SLIPSUM CODE -->

NAO DAT WE KNOE HOO U R, I KNOE HOO IM. IM NOT MISTAEK! IT ALL MAKEZ SENSE! IN COMIC, U KNOE HOW U CAN TELL HOO TEH ARCH-VILLAINS GOIN 2 BE? HEZ TEH EGSAKT OPPOSIET OV TEH HERO. AN MOST TIEMS THEYRE FRENZ, LIEK U AN ME! I SHUDVE KNOWN WAI BAK WHEN... U KNOE Y, DAVID? CUZ OV TEH KIDZ. THEY CALLD ME MISTAH GLAS.

NAO DAT WE KNOE HOO U R, I KNOE HOO IM. IM NOT MISTAEK! IT ALL MAKEZ SENSE! IN COMIC, U KNOE HOW U CAN TELL HOO TEH ARCH-VILLAINS GOIN 2 BE? HEZ TEH EGSAKT OPPOSIET OV TEH HERO. AN MOST TIEMS THEYRE FRENZ, LIEK U AN ME! I SHUDVE KNOWN WAI BAK WHEN... U KNOE Y, DAVID? CUZ OV TEH KIDZ. THEY CALLD ME MISTAH GLAS.

TEH PATH OV TEH RIGHTEOUS MAN IZ BESET ON ALL SIDEZ BY TEH INIQUITIEZ OV TEH SELFISH AN TEH TYRANNY OV EVIL DOODZ. BLESD IZ HE HOO, IN DA NAYM OV CHARITY AN GUD WILL, SHEFERDZ TEH WEAK THRU TEH VALLEY OV...

CSS

.navbar{
    position:fixed;    
}

JavaScript

$(document).ready(function(e) {
        
        $('#nav ul li a').bind('click', function(e) {
            e.preventDefault();
            $('html,body').animate({scrollTop: $(this.hash).offset().top});                                                         
        });
    });