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+# Phase 1: Core Foundation - Context
+
+**Gathered:** 2026-03-10
+**Status:** Ready for planning
+
+<domain>
+## Phase Boundary
+
+Establish the project structure and fundamental architecture patterns that all other components build upon. This phase delivers the foundation: Vite + TypeScript + Canvas setup, game loop, event system, basic Tile model, and configuration.
+
+</domain>
+
+<decisions>
+## Implementation Decisions
+
+### Grid Configuration
+- Grid size: **16 columns × 10 rows** (160 tiles, 80 pairs)
+- 16 unique tile types, each appearing 10 times
+
+### Tile Graphics
+- **Emoji tiles** using 16 nature element emojis:
+  - 🌟 ⭐ 💫 ✨ 🌙 ☀️ 🔥 💧 🌿 ⚡ 🧊 🪨 🌸 🍃 🌊 🍄
+- **Card style** tiles: big emoji in center, rounded corners, subtle shadow
+- **Highlight ring** to show tile selection
+
+### Configuration
+- All game constants in **src/config.ts** as typed TypeScript
+- Configurable items:
+  - Grid dimensions (rows, columns)
+  - Tile size and gap/spacing
+  - Emoji set (array of 16 emojis)
+  - Color palette (background, selection, etc.)
+
+### Claude's Discretion
+- Exact project folder structure
+- Event emitter implementation details
+- Game loop implementation specifics
+- Tile model exact properties
+
+</decisions>
+
+<specifics>
+## Specific Ideas
+
+- 16×10 widescreen grid layout (not the typical square)
+- Nature-themed emoji set for a cohesive visual feel
+
+</specifics>
+
+<code_context>
+## Existing Code Insights
+
+### Reusable Assets
+- None yet (greenfield project)
+
+### Established Patterns
+- Research recommends: Vite 7.x, TypeScript 5.x, HTML5 Canvas
+- No game framework needed for this scope
+
+### Integration Points
+- This is Phase 1 — everything builds on this foundation
+
+</code_context>
+
+<deferred>
+## Deferred Ideas
+
+None — discussion stayed within phase scope.
+
+</deferred>
+
+---
+
+*Phase: 01-core-foundation*
+*Context gathered: 2026-03-10*