[Hustle Pro] Change location & color of the X (close) button on Slide-in & add a timer

What’s the CSS that’ll move the X (close) button for the slide-in feature? I don’t see myself using padding or margin adjustments because it needs to be on the bottom left of the slide-in (for a top-right slide-in on a desktop comp screen, it’d be better if the X button was on the bottom-left, closest to the visitor). Also, can you tell me the CSS that’ll change the color and size of the X?
Lastly, when it comes to slide-ins, it can be important to have a visible countdown timer on it so that the visitor can see he or she won’t need to find an X to close it. (This gets the visitor to continue his or her focus on the page in front of them, too.) Is there code I can add that’ll put a visible (7 sec) countdown timer on the slide-in?