JS how to convert seconds into hours, minutes and seconds display

When we count down, the back end often returns *** second , You need the front-end to display itself on the page in hours, minutes and seconds . How to convert ？

   //  Written in mouned in ：
   let time = this.secTotime(61);
   console.log(" Convert to minutes and seconds yes ",time);
   // methods:
  secTotime(s) {
    
      var t = '';
      if(s > -1){
    
        var hour = Math.floor(s/3600)
        var min = Math.floor(s/60) % 60
        var sec = s % 60
        if(hour < 10) {
    
          t = '0'+ hour + ":"
        } else {
     
          t = hour + ":"
        } 
        if(min < 10){
    
          t += "0"
        } 
        t += min + ":"
        if(sec < 10){
    
          t += "0"
        } 
        t += sec.toFixed(0)
      } 
      return t
    },