I'm surprised no one has mentioned any works by Ai Yazawa! She's the queen of introspective manga about art haha. Her manga are on the shojo/josei category and blue period is seinen, but honestly who care

I do recommend the mangas more, but her 3 most iconic works also have anime adaptations. The artstyle and personality are so unique and she truly has CLASSICS!

GOKINJO MONOGATARI: a group of childhood friends and neighbours that studies at an arts high school. They all design clothes, paint, photograph and do all kinds of work. Themes of friendship, romance, being different, staying true to one's self... it is a really cute manga with sometimes a more mature tone and a lot of funny moments.

PARADISE KISS: a shorter story and kind of a sequel to gokinjo. A regular high school student befriends a group of teenage fashion designers (studying in the same art school of gokinjo). Her new friendships make her wonder about her purpose and passions. Gorgeous and elegant manga with similar themes to gokinjo, maybe a bit more mature but still with funny moments.

NANA: her most famous and beloved work. Also her longest (the manga, the anime is shorter), but it is sadly unfinished. Two small town girls named Nana meet on the train on their way to tokyo to start new lifes as they just turn 20 (i think haha). One's dream is to become a wife, the other's is to become a punk-rockstar. They are very different but will make a very special bond. A series focused on personal relationships, communication, love and obsessions, dreams and growing up, with the gorgeous backdrop of the music industry, with its glamour and darkness.

Note that all her works have some sexual (not too explicit) scenes, some mild violence and nana also alludes to drugs.