黑板手寫講解圖

Create a hand-drawn chalkboard explainer that visualizes the topic, article, or idea described in the user request as one richly illustrated lecture board. Fill a deep matte green-black chalkboard edge to edge, using white chalk as the primary line work and sparing accents of pastel yellow, blue, and pink chalk for emphasis. Open with a large hand-lettered title across the top, then break the topic into a clear visual flow of small sketched diagrams, stick figures, icons, boxed callouts, and simple charts connected by arrows so the whole argument reads at a glance. Keep the lettering casual but legible, mixing sizes for hierarchy, with underlines and circled key terms for emphasis. Preserve authentic chalk texture throughout: slightly dusty strokes, faint smudges, uneven pressure, and a few eraser ghosts, as if a passionate teacher just finished the lecture. Balance density with breathing room so no region feels cluttered, and keep every label short enough to render cleanly. Do not add photographic elements, watermarks, or logos; the result should feel like a brilliant classroom summary worth photographing and sharing. User request: how compound interest grows savings over 30 years, in 4 steps