Motion

The Motion domain owns terminology, review procedure, and evidence-bounded practice guidance for product-layer motion.

Scope Boundary

In scope: naming observable motion, reviewing declared behavior, distinguishing heuristics from measured contracts, and identifying evidence needs.

Out of scope: universal timing or easing rules, unmeasured performance claims, and permission to add animation or decorative properties to reusable Layout pattern CSS.

Start Here

Task	Route
Choose a behavior from the user task.	Motion Decision Tree
Record states, owners, interruption, and evidence.	Motion Brief
Build a scroll-driven product story and inspect runnable examples.	Scroll-driven Story and Scroll Story Lab
Keep the page fixed while navigating between full-screen chapters.	Full-viewport Scene Navigation and runnable example
Apply feedback, disclosure, modal, reorder, progress, and drag contracts.	Motion Interaction Recipes

These workflows and worked cases are usable experimental guidance. Expected-result tables are test designs; actual product, engine, and reader evidence must be recorded separately. Review on a failed task, a source change, or a changed ownership contract.

Documents

• Motion Vocabulary maps observed behavior to implementation-neutral terms while preserving ambiguity.
• Motion Review Workflow structures evidence-first review and remediation.
• Motion Practice Reference classifies mechanics, heuristics, platform notes, and unsupported claims.
• Observed Choreography Transcription transcribes an observed scroll choreography into Scene Composition Contract vocabulary.

Domain Contract

See StyleGallery Domains for lifecycle, provenance, page membership, and staleness rules.

IA Navigation

Parent: StyleGallery. Next: Motion Decision Tree.