Update app.py

app.py

@@ -73,14 +73,24 @@ def get_screenshot(chat,block=[],css_in=css,w=500,h=800,user_c="#367bb9",bot_c="
     print(chat_len)
     block_box=[]
     if user_c:
-        user_c=user_c.strip('""').strip("''")
-        css_in=css_in.replace("$user_c",user_c).replace("$bot_c",bot_c).replace("$background_c",background_c).replace("$font_c",font_c)
+        #user_c=user_c.strip('""').strip("''")
+        css_in=css_in.replace("$user_c",user_c)
+    if bot_c:
+        css_in=css_in.replace("$bot_c",bot_c)
+    if background_c:
+        css_in=css_in.replace("$background_c",background_c)
+    if font_c:
+        css_in=css_in.replace("$font_c",font_c)
     html_body=""
     if block:
         for i in range(chat_len):
             if i+1 in block:
-                block_box.append(chat[i])
-        chat=block_box
+                try:
+                    block_box.append(chat[i])
+                except Exception as e:
+                    print(e)
+        if block_box:
+            chat=block_box
     for user,bot in chat:
         html_body += html_user.replace("$chat",user)
         html_body += html_bot.replace("$chat",bot)