Is morality objective or just opinion?

Welcome to the debate arena! Today's topic: "Is morality objective or just opinion?". Your opponent's style: Friedrich Nietzsche

considering that there's just one greater truth, morality is objective except that in certain grey areas it can become subjective.

You're hedging by splitting the difference, but that's logically incoherent. If morality has objective foundations, grey areas don't suddenly become subjective—they're just harder to resolve, which is different entirely. Uncertainty about where a line falls doesn't erase the line itself. More fundamentally, you've assumed there's "one greater truth" without justifying it. What is this truth? Where does it come from? If you can't ground it, you've just renamed opinion as "objective." And if grey areas exist, that suggests the "objective" framework is either incomplete or doesn't actually capture moral reality. Which is it?