Mandarin has 3 hurdles: tones, characters, and speaking confidence. SinoSpark solves all three: 1. Visual Tone Contours: Real-time acoustic pitch curves graph your voice against native tones. 2. Calligraphic Canvas: Stroke-by-stroke character tracing on Xuan paper. 3. Conversational AI Tutor: Natural voice calls, shadowing sprints & instant corrections. 4. Graded Library: Classical poetry, stories & smart web reader.