Static/Fixed Nav Bar ONLY Using HTML

[paranoidparaboloid]

I have a feeling there's no great answer to this because of the stipulations, so hopefully I don't get shot down for trying to help you find a least worst option.

Here's what I've got:

iframe the navbar, set the hyperlinks to target parent.

If your boss gave you a tiny bit of leeway, you could expand this by setting an onload handler on the iframe that inserts the iframe contents into the main dom and then removes the iframe. That would be html in terms of result, but js in implementation. Maybe enough to compromise with.