⚠️ File Access Restriction

The browser is blocking access to the Excel files due to CORS policy when opening the HTML file directly.

Solutions:

1. Run a local server (recommended):
   • Python: python -m http.server 8000
   • Node.js: npx serve .
   • PHP: php -S localhost:8000
   Then visit http://localhost:8000
2. Use the fallback sample data (current): The app will work with representative sample data
3. Upload custom files: The file upload feature still works for custom datasets