Offline Dialog helpful suggestion
Since no way to capture email use this type of dialog = = => Offline - Please Leave Message w/Phone # & Email For Quick Response
For Online insructions this is another good selection of dialog = = => Chat Now - Type At Bottom & Leave Phone # Or Email For Question Then Hit Enter Key On Your Keyboard
Also make chat "Type here and press enter" text in black as it's very easy to miss and clients request it. It's too transparent in contrast to the chat box gets lost.