If I recall correctly, Nxt does implement the servlet through Jetty but the pages are dynamic through JavaScript.
JavaScript (JQuery for example) can server dynamic content.
Here is a tutorial on how to make a
simple jetty web app.This could be a good starting point for creating a wallet.Then the JQuery will make API calls to Qora wallet and an HTML wallet can be real.
Then Bootstrap can be integrated as well to make the HTML wallet more "fancy".