CodePen Embed - Stopwatch

<div class="wrapper">
  <div class="container">
    <div class="icons" id="btn-start-stop">
        <span class="stop-watch">
          <span class="sw-parts">
            <span class="sw-parts2" id="icn-clock-line"></span>
          </span>
        </span>
        <span class="label" id="label-start-stop">START</span>
      </div>
    <div class="clock">
      <p><span id="hr">00</span>:<span id="min">00</span>:<span id="sec">00</span></p>
    </div>
    <ul class="clockline" id="clockline">
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    </ul>
    <div class="btn btn-reset" id="btn-reset">
      <span class="bl-parts"></span>
      <span class="bl-parts"></span>
      <span class="btn-label">RESET</span>
    </div>
  </div><!-- /.container -->
</div><!--/.wrapper -->

@import "compass/css3";
$boxWidth: 50;
html,body{
  width:100%;
  height:100%;
  background: radial-gradient(50% 16%, circle, #219eb0 32%, #3f679d 88%);
}
.wrapper{
  position:relative;
  width:100%;
  height:100%;
}

.container{
  width:320px;
  height:320px;
  margin:auto;
  position:absolute;
  top:0;
  bottom:0;
  left:0;
  right:0;
  background: linear-gradient(to bottom, #0c3d69 16%, #116c97 95%);
  box-shadow:0 4px 36px 0 rgba(0,0,0,0.5);
  border-radius:8px;
  overflow:hidden;
  
}

.icons{
  position:absolute;
  width:48px;
  height:48px;
  text-align:center;
  cursor:pointer;
  top:4px;
  left:8px;
  .stop-watch{
    display:block;
    width:24px;
    height:24px;
    position:absolute;
    left:0;
    right:0;
    top:50%;
    margin:-10px auto 0;
    border: 2px solid #f8f8f8;
    border-radius:24px;
    //margin:4px auto;
    &::before{
        content:"";
        display:block;
        width:10px;
        height:2px;
        background:#f8f8f8;
        position:absolute;
        top:-6px;
        right:0;
        left:0;
        margin:0 auto;
        transform:top 0.2s;
      }
     &::after{
        content:"";
        display:block;
        width:2px;
        height:4px;
        background:#f8f8f8;
        position:absolute;
        top:-3px;
        right:-3px;

       transform:rotate(45deg);
      }
    &.sw-click::before{
      top:-3px;
    }

    .sw-parts{
      display:block;
      position:absolute;
      top:0;
      bottom:0;
      left:0;
      right:0;
      margin:auto;
      width:4px;
      height:4px;
      border-radius:4px;
      background:#F8f8f8;

      .sw-parts2{
        display:block;
        width:2px;
        height:9px;
        background:#f8f8f8;
        position:absolute;
        top:2px;
        left:1px;
        
      }
      #icn-clock-line{
        transform-origin:50% 0;
        transform:rotate(180deg);
        transition:transform 0.5s ; 
      }
    }
  }
  .label{
    color:#FFF;
    text-align:center;
    position:absolute;
    bottom:-1rem;
    left:0;
    right:0;
    margin:auto;
    font-size:0.75rem;
    font-family: 'Share Tech Mono',sans-serif;
  }
}

.clock{
  p{
    position:absolute;
    color:#FFF;
    text-align:center;
    top:144px;
    left:0;
    right:0;
    margin:0 auto;
    font-family: 'Share Tech Mono',sans-serif;
    font-size:2rem;
    font-weight:300;
  }
}
  
.clockline li{
  width:1px;
  height:20px;
  border-radius:2px;
  background:#f8f8f8;
  position:absolute;
  left: 160px;
  top: 160px;
  //Half size of a circle
  $r: 112;//224px cirlcle
  
  @for $i from 1 through 100{
    //What I want to repeat
    &:nth-child(#{$i}){
      $angle:450 + (360 / 100) * $i;
      $radian: (360 / 100) * (pi()/180) * $i;
      $x: $r * cos($radian) + px;
      $y: $r * sin($radian) + px;
      transform-origin:100% 0%;
      transform: translate($x,$y) rotate( $angle + deg) ;
      @if ($i % 5) == 0 {
        height:32px;
      }
    }
  }
}

.btn{
  cursor:pointer;
}

.btn-reset{
  //shape
  width:48px;
  height:48px;
  //border:1px solid #f8f8f8;
  //border-radius:48px;
  position:absolute;
  top:4px;
  right:8px;
  box-sizing:border-box;
  //padding:10px;
  opacity:0.5;
 
  transition:opacity 0.2s;
  
  
  .bl-parts{
    display:block;
    position:absolute;
    width:24px;
    height:24px;
    border-top:2px solid #f8f8f8;
    border-right:2px solid transparent;
    border-left:2px solid transparent;
    border-radius:50%;
    transform:rotate(45deg);
    top:10px;
    left:10px;
     transition:transform 0s;
    
    &::after{
      content:"";
      display:block;
      width:0;
      height:0;
      border-top:8px solid transparent;
      border-right:8px solid #f8f8f8;
      border-left:8px solid transparent;
      position:absolute;
      top:2px;
     // transform:rotate(-1deg);
      left:8px;
      top:-2px;
    }
  }
  .bl-parts:nth-child(2){
    transform:rotate(225deg);
    
  }
  &.br-click{
    .bl-parts{
      transform:rotate(405deg);
    }
    .bl-parts:nth-child(2){
    transform:rotate(585deg);
  }
  }
}

.btn-label{
  width:100%;
  color:#FFF;
  text-align:center;
  position:absolute;
  bottom:-1rem;
  font-size:0.75rem;
  font-family: 'Share Tech Mono',sans-serif;
}

View Compiled

(function($,doc,win){
  //Variables
  var hour = $('#hr');
  var min = $('#min');
  var sec = $('#sec');
  var liNum = 75;
  var flip = false;
  var intervalCounter = 0;
  //Buttons
  var btnStartStop = $('#btn-start-stop');
  var labelStartStop = $('#label-start-stop');
  var btnReset = $('#btn-reset');
  //Elements for Animations
  var icnClockLine = $('#icn-clock-line');
  var icnClockLineDeg = 180;
  var clockLines = $('.clockline').find('li');
  var clockLines_arr = [];
    for (var i = 0; i < clockLines.length; i++) {
        clockLines_arr.push(clockLines[i]);
    }
  //Time
  var currentTime = 0;
  //States
  var stop = true;
  //Method
  var sWatchMethod ={
    timer: function(){
      var interval = 10;
      time = setInterval(function() {
                intervalCounter +=interval;
                if (!stop) {
                 
                  if((intervalCounter%1000)==0){
                    currentTime += 1000;
                    var appendHour = currentTime / (1000 * 60 * 60) | 0; 
                    var appendMinute = currentTime % (1000 * 60 * 60) / (1000 * 60) | 0;
                    var appendSecond = currentTime  % (1000 * 60) / 1000 | 0;
                  
                    appendHour = appendHour < 10 ? "0" + appendHour : appendHour;
                    appendMinute = appendMinute < 10 ? "0" + appendMinute : appendMinute;
                    appendSecond = appendSecond < 10 ? "0" + appendSecond : appendSecond;
                    hour.html(appendHour);
min.html(appendMinute);
sec.html(appendSecond);
        
                    }
                  
                  //------
                  
                    var target = $('#clockline li').eq(liNum);
          
                    if(!flip){
                    target.css('background','#339dac');
                    }else{
                      target.css('background','#fff');
                    }
                    
                    liNum += 1;
                    if(liNum>100){
                      liNum=0;
                    }
                    if(liNum ==75){
                      flip =!flip;
                    }
                }

            }, 10); 
    },
    startAndStop: function(){

      $('#btn-start-stop .stop-watch').addClass('sw-click');
      setTimeout(function(){
        $('#btn-start-stop .stop-watch').removeClass('sw-click');
      },200);
      stop = !stop;
      if(!stop){
      labelStartStop.html('STOP');
        if(!intervalCounter){
         sWatchMethod.timer();
        }
      }else{ 
     
      labelStartStop.html('START');
      //clearInterval(time);
      //clearInterval(time2);
      }
      
      
      btnReset.css('opacity',1);
      $('.btn-reset .bl-parts').css('transition','transform 0s');
      btnReset.removeClass('br-click');
      setTimeout(function(){
      $('.btn-reset .bl-parts').css('transition','transform 0.5s');
        },200);
    },
    reset: function(){
      if(!stop){
        stop = !stop;
        labelStartStop.html('START');
      }
      clearInterval(time);
      if(intervalCounter){
      currentTime = 0;
      intervalCounter = 0;
      hour.html("00");
      min.html("00");
      sec.html("00");
      liNum = 75;
      flip = false;
      for (var i = 0; i < clockLines.length; i++) {
        $('#clockline li').eq(i).css('background','#fff');
      }
      
      $(this).css('opacity',0.5);
      $(this).addClass('br-click');
      }
    },
    init: function(){
      btnStartStop.on('click',sWatchMethod.startAndStop);
      btnReset.on('click',sWatchMethod.reset); 
    }
  }
  
  $(document).ready(sWatchMethod.init);
  }(jQuery,document,window));

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