I’ve come across them twice. Once on a backpacking trip in the Sierras. And the second time on my property here in Montana.
They are damn scary when it’s just you ... and them.
I was elk hunting alone in Montana years ago and sitting with my back to a thicket of brush looking over a big valley. Just as it was getting dark and it was time to pack it in a damn cougar let lose with a howl in the brush behind me.
Rifle had a scope on it so it was worthless, walked the whole way out with my handgun out, almost got frostbite on that hand. :)
The good news you saw them, it’s the ones you don’t see I worry about. Stealthy animals.