JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<div id="timeMin">
1
</div>
<button type="button" id="startbtn">
start
</button>
<br><br>
<div id="clock">
00:00
</div>

JavaScript

$(document).ready(function(){
	var timeVal = parseInt($('#timeMin').text());
  var mins = 60;
  $("#startbtn").click(function(){
  	setInterval(time, 1000)
  });
  
  function time(){
   if (timeVal > 0) { 
     if (mins > 0){
     	if (mins <= 10){
          console.log(mins);
          $("#clock").html(timeVal+" : 0"+(mins-1));
          mins -= 1;
      } else {
          console.log(mins);
          $("#clock").html(timeVal+" : "+(mins-1));
          mins -= 1;
      }
    } else if (mins === 0) {
        timeVal -= 1;
        mins = 60;
    }
   }
 }
});