Celestial Style is a collection of 14 books that make up part of the Crafting Motifs library. Reading these chapters allows access to the Celestial Style for crafting. Chapters (or rarely the entire book) can be obtained as a possible weekly quest reward for completing the Assaulting the Citadel Trial, the Mage's Tower Trial, or the Oldest Ghost Trial. (Coffer types differ between Normal and Veteran modes) Chapters are a guaranteed drop in Veteran Hard Mode.
Learning all 14 crafting motifs earns the achievement Celestial Style Master.