pls help me find this movie!!!!

okay so i don’t have the best description bc i watched this as a kid and it’s a core memory
i only remember one scene and it’s an animated movie (maybe an anime??) and its this very eerie looking robot in a place that’s just red rocks and the colouring is just very red and the robot is next to a girl who’s crying maybe? and it ends with the robot falling off one off the edge of the red cliff and dying AND IDK WHERE i watched this as a kid but i am desperately hoping someone is obsessed w this movie and knows exactly what i’m taking abt but yh ty!!