Message to Alert Respondent when Constant Sum Reached?

Hi everyone,

Brand new to the site and after searching the forum, I've found similar questions but haven't found a solution yet. Using a Constant Sum (Sliders) question, I'd like to achieve the following two things:

1) Display how much is left out of the 100 I am giving the respondent to allocate;
2) Have a custom pop-up message displayed once they've allocated the 100.

I have specified the Must Total option and made this a Force Response question.

Thank you!