Countdown Timer based on Elapsed Time

Hi! So basically, I want to know if there is a way to change a text that countdowns 24 hours after an event is true… for example

I press a button that triggers a daily event, from that point on an elapsed time is saved. Then after 24 hours, the event will reset.
Now I want to put up a timer that counts down 24 hrs after the event is true up to the next event after 24 hours.

Thank you kindly