What does the quotation ''Stay gold, Ponyboy, stay gold'' mean in the book called Outsiders?

In this quote, Johnny is reminding Ponyboy to hold into the good things..... his youth and innocence. It would be easy for Ponyboy to succumb to the hardness and anger, so often felt by the other boys in the gang. Johnny doesn't want that life for Ponyboy, he wants him to stay true to the boy he is, as well as to embrace his own dreams.