Modify r-2 prompt and change r-2 model to nano

llm_generator.py

@@ -316,10 +316,12 @@ def revise_app_code(brief, file_paths, html_content,image_present,image_data,rep
     The entire attachment will be in the same directory as the index.html file available through Javascript fetch requests.
 
     Return ONLY the complete content of a single file named 'index.html' as plain text with no explanations. Do NOT return any JSON or additional files. Include all necessary HTML, CSS, and JavaScript inline.
-    If external libraries are used, ensure to use the latest stable versions to generate up-to-date, working code. DO NOT use deprecated syntax.
+    If external libraries are used, use the latest stable versions to generate up-to-date, working code. 
+    **DO NOT use deprecated syntax.**
     Always use jsDelivr to load external libraries unless the brief explicitly instructs otherwise.
     Ensure all JavaScript regex literals are syntactically valid. 
     For splitting text by lines, use ONLY **text.split(/\r?\n/)** IF REQUIRED.
+    IF marked library is used, DO NOT use marked() 
     Make sure the code has NO syntax errors."""
 
     # resp = openai.ChatCompletion.create(
@@ -357,7 +359,7 @@ def revise_app_code(brief, file_paths, html_content,image_present,image_data,rep
 
         else:
             data={
-                "model": "gpt-5-mini",
+                "model": "gpt-5-nano",
                 "messages": [
                     {
                         "role": "user",