CODE EXAMPLE FOR JAVASCRIPT

js countdown

/** https://www.youtube.com/watch?v=x7WJEmxNlEs */
//timeInMins repersent time in minutes. eg: timeInMins = 5 --> 5 minutes
function timer(timeInMins) {
    const demo = document.getElementById("demo");
 
    console.log("timeInMins: " + timeInMins);

    let time = 60 * prepareTime;

   setInterval(function () {
        let minutes = Math.floor(time / 60);
        let seconds = time % 60;

        minutes = minutes < 10 ? '0' + minutes : minutes;
        seconds = seconds < 10 ? '0' + seconds : seconds;
        demo.innerHTML = `${minutes}:${seconds}`;
        time--;
    }, 1000);


}