In Jain Dharma, one should not try to change one’s natural body or complexion out of attachment, pride, or dislike.

Jainism teaches:

• Accept the body as it is
• Do not become attached to outer appearance
• Focus on the soul, not the skin color
• Practice ahimsa, satya, aparigraha, and self-discipline

If by “change” you mean using artificial means only to look different, Jain values would generally encourage contentment and non-attachment instead of such change.

So, a Jain person should not seek to change fair to dark or dark to fair out of vanity or aversion. The true goal is inner purity, not outer change.