Add CountDown Timer Function to all array elements

Hi Guys, I’m creating this vanilla JavaScript Project in which, one can add a custom event and its date to the local storage of the browser and upon clicking any event it shows a modal with a timestamp(a countdown timer with seconds) that is remaining for the completion of the event.

My question is:-
How can I wrap this function upon all elements(events) of the array that is returned from local storage of the browser and run it simultaneously with each event every second, when the site is visited by a user?

Please help with this :slightly_smiling_face: