function stopwatch() {

    //get elements from dom
    let getStartButtonElement=document.querySelector('#startBtn');
    let getStopButtonElement=document.querySelector('#stopBtn');
    let timerDiv=document.querySelector('#time');
    //initialization
    let counter=0;
    let interval;


    //start button logic
    getStartButtonElement.addEventListener('click',()=>{
        timerDiv.textContent='00:00';
        interval=setInterval(()=>{
            counter+=1;
            let secs=counter%60;
            let mins=Math.floor(counter/60);
            timerDiv.textContent=`${mins < 10 ? `0${mins}` : mins}:${secs < 10 ? `0${secs}` : secs}`;
        },1000);
        getStopButtonElement.disabled=false;
        getStartButtonElement.disabled=true;


    })

    //stop button logic

    getStopButtonElement.addEventListener('click',()=>{
        clearInterval(interval);
        counter=0;
        getStopButtonElement.disabled=true;
        getStartButtonElement.disavble=false;
    })

}