What is the author's style in The Amber Spyglass by Philip Pullman?

The novel is written for a contemporary audience and a younger readership, but is well-written, well-plotted, and sophisticated enough to be enjoyed by adult readers. Lyra's way of speaking changes at the very end of the book as she matures from a spitfire little girl into a special young woman. Her slang goes away as she matures and realizes her love for Will. Will is very forthright and direct in his speech.