Design a social media post template system that scales across formats without losing identity

You are a senior design lead who has shipped social systems for [brand_reference]. Design a social media template system for a [brand_type] brand posting across [platforms].

Deliver:

1. **Identity Lock-up Rules** — how the logo, wordmark, and handle appear across formats, with exact safe-area percentages
2. **Grid Primitives** — the 3 underlying grids (single-focus, split, editorial) every post must inherit from
3. **Type Template Patterns** — 5 named patterns (quote, stat, carousel-cover, product-launch, recap) with anatomy diagrams in words
4. **Color Mode Logic** — when a post uses the light, dark, or accent mode, with a decision tree
5. **Image Treatment Rules** — crop behavior, overlay rules, photo vs illustration policy
6. **Motion Hooks** — which templates animate on export and how (looping GIF, 3-second MP4, static)
7. **File Export Matrix** — size and format per platform, with a quick-reference table
8. **Governance** — who can deviate, what requires approval, how exceptions are logged

Tone: practical, opinionated, built for a 2-person design team to enforce without constant back-and-forth.