Strong rule: style --- 3D Pixar ---. Professor Leo waving goodbye enthusiastically, standing in front of a modern digital blackboard with a glowing 'A+' and a big winking smiley face. Warm, inviting colors.
Character appearance reference (MUST match exactly):
- Профессор Лев: 3D Pixar style, young energetic male teacher, around 30 years old, wearing round glasses, a cozy green sweater over a white collared shirt, neat brown hair, kind smile, expressive and friendly face, highly detailed, soft lighting.
