> Like I mentioned below, as a self taught web programmer, it was years before I came across a modulus in a real-world situation.

So? Like I mentioned in response to that, modulus isn't necessary for FizzBuzz.

> Again, just listing "HTML5, CSS3, JavaScript." by itself as a minimum qualification doesn't specify what level of knowledge is expected of you.

FizzBuzz doesn't require much depth of knowledge in the target programming language. If you are can handle assignment, addition, conditional logic, and any one of iteration, jumping, or recursion (note that some language may not support all three of those, so which are available depends on language), you can do FizzBuzz.

What FizzBuzz does require (assuming you haven't already studied it and memorized a solution in the language given) is being able to think through a dirt simple problem and apply a programming language to it. It identifies people with minimal programming skills as distinct from those who are limited to cargo cult copypasta (well, again, except that memorization means it can produce false positives.)