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+## ADDED Requirements
+
+### Requirement: Renderer-agnostic map definitions
+The `@trails-cool/map-core` package SHALL provide map configuration data usable by any rendering engine.
+
+#### Scenario: Tile source definitions
+- **WHEN** a renderer needs tile layer URLs
+- **THEN** `map-core` provides base layer and overlay layer configs with URL templates, attribution, and zoom limits
+
+#### Scenario: Route color palettes
+- **WHEN** a renderer needs to color a route by surface, highway, grade, or other mode
+- **THEN** `map-core` provides the color mapping and color functions for all supported modes
+
+#### Scenario: POI category definitions
+- **WHEN** a renderer needs POI icons, colors, and Overpass queries
+- **THEN** `map-core` provides the full category configuration
+
+### Requirement: No rendering dependencies
+The package SHALL have zero dependencies on any rendering library (Leaflet, MapLibre, React, DOM).
+
+#### Scenario: Import in any environment
+- **WHEN** `map-core` is imported in Node.js, a browser, or React Native
+- **THEN** it works without errors — no DOM APIs, no rendering side effects