I tend to go by two of the dictionary's definitions:
1: The conscious production or arrangement of sounds, colors, forms, movements, or other elements in a manner that affects the sense of beauty, specifically the production of the beautiful in a graphic or plastic medium.
2: The product of these activities.
Now, beauty is in the eye of the beholder. So art can still be plenty of things with that definition.
Here's an example of something I DON'T think of as art: Taking a selfie in the bathroom mirror and posting it somehwere to show off your new hair/clothes/etc. You didn't do it because you thought you looked pretty. Stop lying. You did it to show it off to others and get some positive attention.
Here's an example of something I DO think of as art: A simple photograph of your pet. Sure, it's just about the lowest quality art, imo. But you saw your pet, and decided that you wanted to capture that moment so you could look at it again, or let others look at it. In other words, you found it beautiful in one way or form.
Of course my definition is flawed. And I may not always keep to it myself. But that's the thing with 'art'. Every attempt to properly define what art is throughout the centuries, has failed. And I'm not claiming to be some messiah that figured it all out. It's just what I think of art.