I am a web developer for a major US retailer. I work in html, css and javascript all day. I can create a forward chaining javascript object to evaluate data from a webform to produce the answer you need. You mentioned an example of a backwards chain, but I did not see that attached. If you provide me with the data, I can whip this up for you in a few days.
To clarify, the code will evaluate the given data to consider some secondary variables, like is the animal a reptile or mammal, and then using those secondary variables and additional ones like color or the presence of horns, determine what the animal is. The code will also detect when it does not have enough data to give a singular answer, and will have different output in that case as well.