detailed black-and-white digital drawing, sketch pen style,, Vibrant retro-futuristic megacity, extremely dense towering skyscrapers with glowing windows and intricate details, flying cars and spaceships zooming between buildings, massive curved structures and elevated highways. Bright blue sky with dramatic clouds, energetic atmosphere, heavy traffic of futuristic vehicles, neon and warm interior lights, detailed architecture, cinematic perspective, retro sci-fi style