frame.html

## frame.html
<html>
<head>
<style>
  a{
    display: block;
    margin: 2em 1em;
  }
</style>
</head>
<body>
  <a name="anchor-1" href="#anchor-1">Anchor #1</a>

  <a name="anchor-2" href="#anchor-2">Anchor #2</a>

  <a name="anchor-3" href="#anchor-3">Anchor #3</a>

  <a name="anchor-4" href="#anchor-4">Anchor #4</a>

  <a name="anchor-5" href="#anchor-5">Anchor #5</a>

    <script src="http://zeptojs.com/zepto.min.js"></script>
  <script>
    window.addEventListener('message', function(event) {
      if(anchor = event.data['findElement']) {
        element = $('[name="' + anchor + '"]')
        window.parent.postMessage({"offset": element.offset().top}, "*")
      }
    })

    $(document).ready(function(){
      window.parent.postMessage("ready", "*")

      $('a').click(function(){
        event.preventDefault()
        window.parent.postMessage({"setAnchor": $(this).attr('name')}, "*")
      })
    })
  </script>
  </body>
</html>

## index.html
<html>
<head>
<style>
iframe{
  width: 100%;
  border: 1px solid #888;
  height: 290px;
  margin: 1em 0;
  overflow: hidden;
}
</style>
</head
<body>
  <iframe src="frame.html"></iframe>

  <script src="http://zeptojs.com/zepto.min.js"></script>
  <script>
window.addEventListener('message', function(event) {
  if(event.data == 'ready') {
    sendHash()
  }

  if(anchor= event.data['setAnchor']) {
    window.location.href = '#' + anchor
  }

  if(offset = event.data['offset']) {
    window.scrollTo(0, $('iframe').offset().top + offset)
  }
})

sendHash = function(){
  hash = window.location.hash.substring(1)
  $('iframe')[0].contentWindow.postMessage({"findElement": hash}, '*')
}

$(window).on('hashchange', sendHash)
  </script>
</body>
</html>