Poderia ser O cantor do vento ( Les Secrets d'Aramanth )?
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É o primeiro livro do Wind on Fire (traduzido para o francês como Le Vent de Feu ) trilogia por William Nicholson, publicado em 2000 - 2003. Eu não li o livros eu mesmo, mas foi mencionado em este tópico do Reddit , e a descrição da Wikipedia é mais ou menos em linha com o seu.
Os personagens principais são Kestrel e Bowman, e eles moram em uma cidade chamada Aramanth. Ele realmente tem separação de cores baseada no mérito *, todas as ênfases são minhas:
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"cor diferente"
Using a system based on colour classifications, the governing Examiners dictate what people can wear, where they can live and what jobs they can do. The levels are grey, maroon, orange, scarlet and white, with grey the lowest and white the highest.
Ou de outra página da Web :
The book tells the story of how a sister and brother (Kestrel and Bowman Hath), and their stinky classmate Mumpo, dare to challenge the oppressive social order that operates in the walled city of Aramanth.
Under this system, families can move up and down the social scale depending on their children's success (or otherwise) in school examinations, and on the parents' success (or otherwise) in their careers. High achievement brings not just prestige, but promotion up the colour-coded, socio-economic ladder - from the low-rent tenements of Grey District up through Maroon, Orange and Scarlet to the very topmost district of all, ie White.
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Vá em uma aventura e, eventualmente, confronte algumas criaturas do mal:
This sets in motion a chain of events that eventually results in Kestrel, Bowman and a mentally challenged boy called Mumpo escaping from the city and going on a quest to save their people from an evil entity known as the Morah, which controls a numberless army of malevolent and deadly beings called the Zars.