Kids Reward Sticker Design: Hippo Holding a Giant A+ Sign

Create a clean, vector-style illustration of a friendly hippo holding a large, bold A+ sign. The design should feature crisp lines with no shading or gradients, on a pure white background. The hippo should appear happy and proud, with simple, cartoon-like features suitable for children’s reward stickers. The A+ sign must be clearly visible and proportionate, designed for a die-cut sticker format. Ensure high contrast and a professional, polished look, perfect for printed rewards.