A crystalline underground cave illuminated by ethereal blue bioluminescent algae streaming down ancient stalactites, National Geographic quality geological nature art, massive transparent selenite crystals towering like frozen cathedral spires, underground lake reflecting otherworldly glow, mood of subterranean wonder and ancient geological magic, deep sapphire blue and luminous teal palette with soft ethereal light, dramatic wide composition from cave entrance emphasizing the crystals' monumental scale against the dark cavern walls, shallow depth of field with distant cave passages fading into mysterious darkness, cinematic composition