Fix CORS

.env.example

@@ -5,7 +5,9 @@ POSTGRES_PASSWORD=audio_password
 POSTGRES_DB=audio_classifier
 
 # Backend API
-CORS_ORIGINS=http://localhost:3000,http://127.0.0.1:3000
+# Use "*" to allow all origins (recommended for development/local deployment)
+# Or specify comma-separated URLs for production: http://yourdomain.com,https://yourdomain.com
+CORS_ORIGINS=*
 API_HOST=0.0.0.0
 API_PORT=8000
 
@@ -16,4 +18,5 @@ ESSENTIA_MODELS_PATH=/app/models
 AUDIO_LIBRARY_PATH=/path/to/your/audio/library
 
 # Frontend
-NEXT_PUBLIC_API_URL=http://localhost:8000
+# API URL accessed by the browser (use port 8001 since backend is mapped to 8001)
+NEXT_PUBLIC_API_URL=http://localhost:8001