Design a **long, arched underground passageway** with a **smooth, light-colored ceiling** instead of a rough one. Replace the **graffiti** with **abstract murals** featuring **bright geometric shapes**. Change the **brick walls** to **cement blocks** in varying shades of gray. Remove the existing **fluorescent lighting** and incorporate **soft, ambient lights** embedded in the walls, casting a warm glow. Instead of a bright exit, create a **large, decorative mural** at the end of the tunnel that draws attention.