diff --git a/backend/app/api/design_generator.py b/backend/app/api/design_generator.py
index f7dd15e..ff19836 100644
--- a/backend/app/api/design_generator.py
+++ b/backend/app/api/design_generator.py
@@ -77,26 +77,27 @@ Square format, clean edges for die-cut sticker."""
     # Call Gemini API for image generation
     try:
         async with httpx.AsyncClient(timeout=120.0) as client:
+            # Use gemini-3-pro-image-preview for image generation
             response = await client.post(
-                f"https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-flash-exp:generateContent?key={gemini_api_key}",
+                f"https://generativelanguage.googleapis.com/v1beta/models/gemini-3-pro-image-preview:generateContent?key={gemini_api_key}",
                 json={
                     "contents": [{
                         "parts": [{
-                            "text": f"Generate an image: {style_prompt}"
+                            "text": style_prompt
                         }]
                     }],
                     "generationConfig": {
-                        "responseModalities": ["image", "text"],
-                        "responseMimeType": "image/png"
+                        "responseModalities": ["image", "text"]
                     }
                 },
                 headers={"Content-Type": "application/json"}
             )
 
             if response.status_code != 200:
+                error_detail = response.text[:500] if response.text else "Unknown error"
                 raise HTTPException(
                     status_code=502,
-                    detail=f"AI generation failed: {response.text}"
+                    detail=f"AI generation failed ({response.status_code}): {error_detail}"
                 )
 
             result = response.json()
@@ -112,9 +113,11 @@ Square format, clean edges for die-cut sticker."""
                     break
 
             if not image_data:
+                # Log what we got for debugging
+                import json
                 raise HTTPException(
                     status_code=502,
-                    detail="AI did not return an image"
+                    detail=f"AI did not return an image. Response: {json.dumps(result)[:500]}"
                 )
 
     except httpx.TimeoutException: