Advice on neural net software

Now that I'm retired, I have time to work on a project I've had in mind for years, but I'd like some advice on how and where to get started since it's far afield of my experience. I think it would be best be done with a neural net, but I could be wrong.

The idea is to develop an AI assistant for judging "pleasing" color combinations that could be used by various graphic artists, website developers and fashion designers. The initial inputs would the results of polling as many people as possible, presenting various color pairs and asking for a rating of how well the colors "go together", +2 like to -2 dislike.

The intended output would have two modes: the first being when a given a pair of colors, to predict a rating that the pair might receive in polling; and the second being when given a single color, to suggest one or more color pairs that should get good ratings.

Actual ratings for the predictions would be feed back into the input data to verify and improve accuracy.

I'd like to minimize the learning curve, so any advice on software and how to get started would be greatly appreciated. (I'm planning to develop in C# if that matters.)