Vulva and vagina are not the same thing
The vulva is the external genital area. It includes the outer labia, inner labia, clitoral hood and clitoris, urethral opening, vaginal opening, and surrounding skin. The vagina is the internal muscular canal.
Puberty can make the labia larger, more folded, darker, or more visible. Pubic hair and oil or sweat glands develop too. One inner labium may be longer than the other, and either or both may extend beyond the outer labia.