Imagine a massive undersea highway tunnel stretching for miles beneath the ocean, constructed with sleek, curved glass walls that offer a stunning, immersive view of the aquatic realm. High-tech vehicles glide effortlessly through the tunnel, their lights reflecting off the shimmering glass. Outside, a futuristic world of marine life unfolds—advanced sea drones swim alongside, monitoring the environment. A gentle sea turtle passes by, while a sleek, cyber-enhanced shark glides with precise, mechanical grace. Bioluminescent jellyfish drift lazily, casting a soft, neon glow that illuminates the tunnel, while futuristic sea plants sway gently in the current. The tunnel is illuminated with soft, holographic displays, providing travelers with information about the mesmerizing marine life outside.