Create a high-fidelity mobile app UI mockup for a sleep habit tracker. Display clean smartphone screens on a soft desk background, showing bedtime routine cards, a weekly sleep consistency chart, calming alarm setup, habit streak rings, and a moon and sunrise icon system. Use a vertical 3:4 composition, rounded cards, accessible contrast, modern calming palette of deep navy, mist blue and warm cream, no real brand names, only short abstract placeholder text shapes, no readable sentences, no watermark.