refactor: replace card terminology with emoji/cell in user-facing text

- Page title: "Pikachu Card Matching" → "Pikachu Connect"
- Menu subtitle: "Card Matching" → "Emoji Matching"
- CLAUDE.md: update descriptions to reflect emoji-based game
- game-design.md: "Card Rendering/States" → "Cell Rendering/States"
- README: remove obsolete card asset pack reference
- Internal code names (cardBg, selectedCards) kept as-is

CLAUDE.md

@@ -3,7 +3,7 @@
 This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
 
 ## Overview
-This is a Pikachu card matching game built with Phaser 3 and Next.js. The game implements the classic "Pikachu" card matching rules where players must match identical cards using I, L, U, or Z-shaped connection patterns.
+This is a Pikachu emoji matching game built with Phaser 3 and Next.js. The game implements the classic "Pikachu" matching rules where players must match identical emoji pairs using I, L, U, or Z-shaped connection patterns.
 
 ## Commands
 
@@ -48,22 +48,22 @@ This is a Pikachu card matching game built with Phaser 3 and Next.js. The game i
 1. **Boot** - Initial boot scene
 2. **Preloader** - Asset loading scene  
 3. **MainMenu** - Main menu interface
-4. **PikachuGame** - Main game scene with card matching logic
+4. **PikachuGame** - Main game scene with emoji matching logic
 
 ### Game Logic
-- **Board**: 20x8 grid of cards using standard playing card assets
+- **Board**: 20x8 grid of emoji cells
 - **Matrix System**: 10x22 matrix with border padding (8x20 actual game board)
-- **Matching Rules**: Cards must be identical and connected via valid paths:
+- **Matching Rules**: Cells must contain identical emojis and be connected via valid paths:
   - **I-pattern**: Straight line (horizontal or vertical)
   - **L-pattern**: Single 90-degree turn
   - **U-pattern**: Path extending to board border with two turns
   - **Z-pattern**: Two-turn path through empty cells
-- **Game Features**: New game, hint system, card selection with visual feedback, debug visualization toggle
-- **Testing**: Comprehensive Jest test suite with 90+ test cases covering all patterns
+- **Game Features**: New game, hint system, selection with visual feedback, score/combo/timer, debug visualization toggle
+- **Testing**: Comprehensive Jest test suite with 84 test cases covering all patterns
 
 ### Asset Structure
-- Cards are stored in `public/assets/cards/` with naming convention like `2S.png`, `KC.png`
 - Background image at `public/assets/bg.png`
+- Emoji symbols rendered as Phaser text objects (no image assets needed)
 - Assets are loaded through Phaser's standard asset loading system
 
 ### React-Phaser Communication

README.md

@@ -1,7 +1,6 @@
 ## Credit
 
 Rule: https://www.scribd.com/document/718603193/Pikachu
-Assets: https://natomarcacini.itch.io/card-asset-pack
 
 # Phaser Next.js Template
 

docs/game-design.md

@@ -187,13 +187,13 @@ The game is complete when no visible cells remain on the board (all 160 cells ha
 - Accent color (titles): `#f1c40f` (gold)
 - Text: `#ecf0f1` (light), `#7f8c8d` (muted)
 
-### Card Rendering
+### Cell Rendering
 
-Cards are rendered as Phaser containers with:
-- **Background rectangle:** 50x50px cream (`#faf8ef`) with 1px border (`#d5ceb8`)
+Cells are rendered as Phaser containers with:
+- **Background:** 48x48px rounded rectangle (6px radius) with dark fill and subtle border
 - **Emoji symbol:** 28px centered with padding to prevent glyph clipping
 
-### Card States
+### Cell States
 
 | State | Visual |
 |-------|--------|
@@ -228,7 +228,7 @@ All buttons have hover scale (1.05x) and press feedback (0.95x).
 
 ## Symbol Set
 
-The game uses 24 emoji symbols as card faces:
+The game uses 24 emoji symbols as cell faces:
 
 ```
 😀 😂 🥰 😎 🤩 😴 🤔 😱

src/game/scenes/MainMenu.js

@@ -32,7 +32,7 @@ export class MainMenu extends Scene {
         });
 
         // Subtitle — slide up + fade
-        const subtitle = this.add.text(600, 345, 'Card Matching', {
+        const subtitle = this.add.text(600, 345, 'Emoji Matching', {
             fontFamily: 'Arial', fontSize: 28, color: '#ecf0f1', align: 'center'
         }).setOrigin(0.5).setAlpha(0);
 

src/game/scenes/pikachu-path-renderer.js

@@ -1,4 +1,4 @@
-// Path drawing utilities for connection lines between matched/mismatched cards
+// Path drawing utilities for connection lines between matched/mismatched cells
 
 import { BOARD_WIDTH, BOARD_X, BOARD_Y, CARD_W, CARD_H } from './pikachu-game-config.js';
 

src/pages/index.jsx

@@ -7,8 +7,8 @@ export default function Home() {
     return (
         <>
             <Head>
-                <title>Pikachu Card Matching</title>
-                <meta name="description" content="Classic Pikachu card matching game built with Phaser 3 and Next.js" />
+                <title>Pikachu Connect</title>
+                <meta name="description" content="Classic Pikachu emoji matching game built with Phaser 3 and Next.js" />
                 <meta name="viewport" content="width=device-width, initial-scale=1" />
                 <link rel="icon" href="/favicon.png" />
             </Head>