Design an interior bathroom space inside a natural ice cave structure located in Antarctica. Use natural ice formations as the main material for the walls, floor and ceiling, making sure to retain the icy textures and translucency to maintain the authenticity of the cave. The design should incorporate a balance between the cold, raw beauty of ice and the warmth and comfort of a modern living room. Include minimalist yet functional furniture and soft lighting that complements the reflective properties of ice. The overall aesthetic should evoke a harmonious combination of natural wonder and human comfort, paying attention to how light interacts with the ice to create a serene and brilliant atmosphere.