yeah I got scared for the dog, but those mountin lions are so beautiful I can't
She attacked him, because she is a cat, they attack by instinct. They can even attack if they are scared, weird animals, love them

And yeah if the dog was barking at her, then of course she'd attack him...
I hope the doggie is ok
Why did she ran tho ? Did she hear something and ran away, or did she realize that it's not a threat and decided to leave it alone ?