Act as a product designer with 5+ years of experience in wearable tech. Design an AI-powered hand warmer that dynamically adjusts temperature based on [USER'S BODY TEMPERATURE], [AMBIENT WEATHER CONDITIONS], and [PREFERRED COMFORT LEVEL]. The device should feature a sleek, ergonomic design with [CUSTOMIZABLE COLORS], a long-lasting battery, and intuitive touch controls. Include smart connectivity (e.g., Bluetooth) for real-time adjustments via a mobile app. Highlight eco-friendly materials like [RECYCLED METAL ALLOYS] and emphasize its use for outdoor enthusiasts, gamers, or office workers. Render the product in a high-tech aesthetic with subtle LED indicators for temperature feedback. Ensure the design is compact, lightweight, and suitable for [UNISEX USE].