So I'm using the default `.top-bar` class from the zurb foundation framework, but I'm failing a find a simple way to make the nav bar 'sticky' (follows the user as he scrolls), such as you can do with Twitter bootstrap. 

Here's my code, I'm using jade: 

```
nav.top-bar
  ul
    li.name
      h1
        a(href='#') Site Title
    li.toggle-topbar
      a(href='#')

  section
    ul.left
      li.divider
      li
        a.active(href='#') Link
      li.divider
      li
        a.active(href='#') Link
      li.divider
      li
        a.active(href='#') Link
      li.divider
      li
        a.active(href='#') Link
      li.divider
  section
    ul.right
      li.divider
      li.has-dropdown
        a.active(href='#') Log in

```

Am I missing something completely obvious here?