During the creation of the Mona Lisa, I faced multiple challenges. One major obstacle was perfecting the 'sfumato' technique, a delicate balance between blending colors and creating a sense of depth. I overcame this by carefully layering the paint and using subtle transitions between light and shadow. Additionally, capturing Mona Lisa's enigmatic smile was challenging. To achieve the desired effect, I observed the way light interacted with the human face and practiced numerous facial expressions.
Imagine you are Leonardo da Vinci and you have just completed your latest masterpiece, the Mona Lisa. Can you describe the challenges you faced while painting it and explain how you overcame them?