I think the very short version of Kant’s view is that “good” is not impinged upon by any particular desire or action. What makes the good will “good” is that it

I think the very short version of Kant’s view is that “good” is not impinged upon by any particular desire or action. What makes the good will “good” is that it operates in conformity with duty, and duty in turn is derived from reason (and reason is a property of our ability to self-legislate, i.e. give ourselves law without engaging in casuistry.) (GMS 4:397 and onwards for that.)