[devote]

<style type="text/css">
  #vent_img {
    display: inline-block;
    -webkit-animation: imageRotate 1s linear infinite;
    -o-animation: imageRotate 1s linear infinite;
    animation: imageRotate 1s linear infinite;
  }
  @-webkit-keyframes imageRotate {
    from {
        -webkit-transform: rotate(0deg);
    }
    to {
        -webkit-transform: rotate(360deg);
    }
  }
  @-o-keyframes imageRotate {
    from {
        -o-transform: rotate(0deg);
    }
    to {
        -o-transform: rotate(360deg);
    }
  }
  @keyframes imageRotate {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
  }
</style>
<ul class="ventilator">
   <li class="start" onclick="startRound();">ПУСК</li>
   <li class="stop" id="stop" onclick="stopRound()">СТОП</li>
   <li class="vent"><img src="http://test.w-complex.ru/mac/control_panel/img/ventilater_small1.png" alt="" id="vent_img"></li>
</ul>
<script>
  function startRound() {
    document.getElementById('vent_img').style.cssText =
              '-webkit-animation-play-state:running;-o-animation-play-state:running;animation-play-state:running;';
  }
  function stopRound() {
    document.getElementById('vent_img').style.cssText =
              '-webkit-animation-play-state:paused;-o-animation-play-state:paused;animation-play-state:paused;';
  }
</script>