What is the main point of wadjda's book Bicycle?

This novel is adapted from the award-winning film wadjda by Saudi director Haifaa Al-Mansour. The film wadjda won the Best Film Award in the Future at Venice Film Festival, the Best Film at Sydney International Film Festival and the Best Children's Film at Asia-Pacific Film Award (nomination). It represented Saudi Arabia in the Oscar for Best Foreign Language Film, which was highly praised internationally! The novel tells the story of wadjda, a little girl in Saudi Arabia, who dreams of owning a bicycle but is not allowed by the local religion. She was under pressure from family and society, but finally realized her dream with her unremitting efforts and her mother's understanding and help.