Act as a wearable tech designer with 5+ years of experience in fitness and health monitoring devices. Design a sleek, modern smart belt that tracks [POSTURE CORRECTION], [STEP COUNT], and [CALORIE BURN] in real-time. The belt should feature [ADJUSTABLE VIBRATION ALERTS] for posture reminders, [WATER-RESISTANT MATERIAL] for durability, and [BLUETOOTH CONNECTIVITY] to sync with a companion app. Ensure the design is minimalist, unisex, and suitable for both casual and professional wear. Highlight how the belt seamlessly integrates into daily life while providing actionable health insights. Include details on battery life, charging mechanism, and customizable settings for different user preferences.