transform this interior into a photorealistic underground grotto inspired by ancient roman baths the space should feel carved heavy and timeless like it has existed for centuries do not change the layout walls stairs or proportions keep everything exactly the same spatially but completely redesign the materials and atmosphere all walls floors and ceilings should be made of rough aged stone and plaster with heavy texture and depth the walls should feel carved and imperfect like ancient roman architecture thick weathered slightly uneven with visible wear and erosion no smooth modern surfaces use a strictly neutral monochromatic palette of stone concrete limestone and travertine tones no bright or artificial colors everything should feel natural mineral based and timeless incorporate arched openings carved niches and subtle architectural detailing inspired by ancient roman bathhouses add depth to the walls with recesses and shadow lines so it feels massive and grounded include a hot bath and cold plunge pool integrated into the architecture the pools should feel carved directly out of the stone not placed objects edges should be thick and monolithic water should be still dark and reflective lighting should be extremely moody and atmospheric use hidden indirect lighting soft warm glow from below water surfaces and subtle uplighting that grazes the rough walls to emphasize texture the space should feel dim intimate and slightly mysterious like candlelight without actually showing candles add a light mist or steam in the air to enhance the spa atmosphere especially near the hot bath the space should feel humid warm and immersive the overall feeling should be ancient roman bath luxurious but raw heavy stone architecture immersive quiet powerful timeless like a private bath for an emperor photorealistic ultra detailed textures strong shadows cinematic lighting no modern finishes no polished contemporary look
