Act as a product designer with 10 years of experience in consumer electronics. Design a sleek, modern portable air purifier with real-time air quality monitoring for [home/office/travel] use. The device should feature a [minimalist/tech-inspired/aesthetic] design, a [touchscreen/LED] display showing PM2.5, CO2, and VOC levels, and customizable [color/finish] options. Include innovative details like [UV-C sterilization/HEPA+carbon filter/smart app integration] and emphasize portability with a [compact size/lightweight build/rechargeable battery]. Render the product in a [realistic/3D/stylized] style, showcasing its functionality in a [home/urban/outdoor] setting with clean air visuals. Highlight key selling points like [quiet operation/one-touch controls/auto-adjusting fan speed].