Novice
Some HTML and CSS has been written, but it’s a little (or a lot) broken. Nothing particularly ambitious has been attempted in the HTML/CSS prototype.
Competent
The basic design works and is responsive, and the page(s) are mostly complete. Code could probably be better organized or cleaned up, but the prototype conveys clearly the design concept within a web browser.
Proficient
The design feels solid in the browser, and code is well-organized and documented.
Expert
Every detail in the design has been considered in implementation, with interactive states considered throughout. Accessibility has also been considered and implemented. Are you sure you’re in the right class?