夜间城市健身肖像

Create a cinematic low-light fitness portrait of a confident young woman sitting on modern concrete stairs outdoors at night in a moody urban environment. She is centered in a vertical 2:3 frame, seated casually with one leg extended down to a lower step and the other knee bent upward, one hand resting near a stainless steel water bottle placed by her raised leg. She wears an oversized dark brown pullover hoodie with loose sleeves, fitted black biker shorts, white ribbed crew socks with a small black swoosh-like logo, and chunky gray-and-white running sneakers. Her dark hair is tied back in a slightly messy athletic style, with a natural confident pose; keep the face softly anonymized or out of focus if needed. The setting is architectural concrete: broad gray steps, a tall concrete wall behind her, and exactly 4 warm vertical wall lights glowing along the wall, plus subtle warm strip lighting along stair edges. Background city lights are faint and blurred in the upper right. Use shallow depth of field, realistic photography, soft warm highlights against cool shadows, high dynamic range, detailed fabric texture, natural skin tones, moody cinematic color grading, 35mm portrait perspective, and no text or watermark.