Create a highly realistic vertical 3:4 smartphone selfie photo of an adult female cosplayer at a crowded game/anime convention booth, shot from slightly above chest height with both arms extended toward the camera. She wears an ornate ethereal fantasy costume in {argument name="costume colors" default="pale icy blue, white, silver, and gold"}: a low-cut sculptural bodice with metallic gold trim, translucent flowing gauze sleeves, layered sheer fabric, and a central blue flower ornament. Include exactly 6 prominent costume/accessory elements: 1 floral-and-gold hairpiece with pale blue ribbons on the left side of her dark hair, 1 pair of dangling pearl-like earrings, 1 delicate necklace with a long crystal pendant, 1 ornate structured bodice, 2 translucent sleeve drapes, and 1 central flower-and-gold chest ornament. The background is a busy indoor expo hall with harsh overhead lighting, ceiling trusses, many attendees in casual clothing, and exactly 3 visible large fantasy character displays/posters behind her: one tall illustrated banner on the upper left, one bright central fantasy banner, and one smaller dark blue screen/poster on the upper right. Use natural smartphone flash/ambient lighting, realistic skin texture, shallow depth of field, candid convention atmosphere, no text overlay, no watermark.