diff --git a/.github/workflows/backend-ci.yml b/.github/workflows/backend-ci.yml
index 72ad4a3..c4282b8 100644
--- a/.github/workflows/backend-ci.yml
+++ b/.github/workflows/backend-ci.yml
@@ -1,5 +1,5 @@
 # Copyright (c) 2025 CityLens Contributors
-# Licensed under the MIT License
+# Licensed under the GNU General Public License v3.0 (GPL-3.0)
 
 name: Backend CI
 
diff --git a/.github/workflows/mobile-ci.yml b/.github/workflows/mobile-ci.yml
index 7cc7df0..1c5c117 100644
--- a/.github/workflows/mobile-ci.yml
+++ b/.github/workflows/mobile-ci.yml
@@ -1,5 +1,5 @@
 # Copyright (c) 2025 CityLens Contributors
-# Licensed under the MIT License
+# Licensed under the GNU General Public License v3.0 (GPL-3.0)
 
 name: Mobile App CI
 
@@ -43,7 +43,7 @@ jobs:
         run: flutter build apk --release
       
       - name: Upload APK
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: citylens-app
           path: ./mobile-app/build/app/outputs/flutter-apk/app-release.apk
diff --git a/.github/workflows/web-ci.yml b/.github/workflows/web-ci.yml
index 9cb426b..7552324 100644
--- a/.github/workflows/web-ci.yml
+++ b/.github/workflows/web-ci.yml
@@ -1,5 +1,5 @@
 # Copyright (c) 2025 CityLens Contributors
-# Licensed under the MIT License
+# Licensed under the GNU General Public License v3.0 (GPL-3.0)
 
 name: Web Dashboard CI
 
@@ -40,7 +40,7 @@ jobs:
         run: npm run build
       
       - name: Upload build artifacts
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: web-dashboard-build
           path: ./web-dashboard/dist
diff --git a/backend/app/core/config.py b/backend/app/core/config.py
index eaaf0b9..d7efbdf 100644
--- a/backend/app/core/config.py
+++ b/backend/app/core/config.py
@@ -1,12 +1,13 @@
 # Copyright (c) 2025 CityLens Contributors
 # Licensed under the GNU General Public License v3.0 (GPL-3.0)
 
+import json
 from typing import List, Union, Optional
-from pydantic import AnyHttpUrl, validator, ConfigDict
-from pydantic_settings import BaseSettings
+from pydantic import AnyHttpUrl, field_validator
+from pydantic_settings import BaseSettings, SettingsConfigDict
 
 class Settings(BaseSettings):
-    model_config = ConfigDict(
+    model_config = SettingsConfigDict(
         case_sensitive=True,
         env_file=".env",
         extra='ignore'  # Ignore extra fields from .env
@@ -24,6 +25,23 @@ class Settings(BaseSettings):
     
     # CORS
     BACKEND_CORS_ORIGINS: List[Union[str, AnyHttpUrl]] = ["http://localhost:3000", "http://localhost:8000", "*"]
+    
+    @field_validator('BACKEND_CORS_ORIGINS', mode='before')
+    @classmethod
+    def parse_cors_origins(cls, v):
+        """Allow comma-separated string or JSON array for CORS origins"""
+        if v is None or v == "":
+            return []
+        if isinstance(v, str):
+            # If user provides JSON array string, try to parse
+            if v.strip().startswith('['):
+                try:
+                    return json.loads(v)
+                except json.JSONDecodeError:
+                    pass
+            # Fallback: comma-separated list
+            return [origin.strip() for origin in v.split(',') if origin.strip()]
+        return v
 
     # Database (PostgreSQL with PostGIS)
     POSTGRES_SERVER: str = "db"
@@ -54,6 +72,7 @@ class Settings(BaseSettings):
     OPENWEATHER_API_KEY: Optional[str] = None
     TOMTOM_API_KEY: Optional[str] = None
     AQICN_API_KEY: Optional[str] = None  # WAQI API token from https://aqicn.org/api/
+    GEMINI_API_KEY: Optional[str] = None  # Google Gemini API key for AI chat
     
     @property
     def REDIS_URL(self) -> str:
diff --git a/docker-compose.yml b/docker-compose.yml
index 54293ee..6343ab3 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -85,6 +85,7 @@ services:
     env_file:
       - ./backend/.env
     environment:
+      - BACKEND_CORS_ORIGINS=["*"]
       - POSTGRES_SERVER=postgres
       - POSTGRES_USER=citylens
       - POSTGRES_PASSWORD=citylens_password