Aesthetic treatment for partly yellow teeth/canines and small gaps between teeth. Potential bruxism? (photos)

I am looking for suggestions for potential aesthetic treatments for my partly yellow teeth (with a white tip for whatever reason, mainly the canines) and the small gaps between teeth. (Between incisors, about 1mm) I don't drink red wine and coffee, nor do I smoke. I was told, looking at the canines, this seems to be a case of bruxism (not sure though! And I am not aware of any teeth clenching). Can something be done here to fill the "black triangles"?