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                h1 animation play state

  button#button.btn.btn-warning(type="button", data-status="1") PAUSE


                @import 'nib';
@keyframes move
  0%   { background-color: #8CC152; left: 0; }
  35%  { background-color: #4FC1E9; }
  50%  { background-color: #967ADC; }
  65%  { background-color: #E9573F; }
  100% { background-color: #F6BB42; left: calc(100% - 2em); }

  position: absolute
  left: 0
  background-color: #E6E9ED
  animation move 5s ease-in-out 0s infinite alternate both
    animation-play-state: running
    animation-play-state: paused

$w = 2em
  font-size: 100%
  font-size: 2.4rem
  text-align: center
  list-style: none
  margin: 2em auto 2em
  padding: 0
  max-width: 760px
  display: flex
  flex-direction: row
  justify-content: flex-start
  align-items: center
  padding: .5em 1em
  border-bottom: 1px solid #AAB2BD
  width: 100%
  box-sizing: border-box
    border-top: 1px solid #AAB2BD
  position: relative
  flex: 1
  height: $w
  font-size: 83%
  white-space: nowrap
  padding-right: .5em
  width: 8em
  border-radius: 50%
  width: $w
  height: $w
colors = {
  '1': #A0D468,
  '2': #FFCE54,
  '3': #4FC1E9,
  '4': #E9573F,
  '5': #967ADC,
  '6': #D770AD,
  '7': #4A89DC,
  '8': #DA4453,
  '9': #5D9CEC,
  '10': #ED5565
for key, value in colors
    background-color: value

  text-align: center
  display: block
  font-size: 112%
  text-transform: uppercase
  cursor: pointer
  margin: 0 auto 1em
  padding: .5em 1em
  width: 100%
  max-width: 300px
    cursor: default


                const d = document;
const statusList = [
  {key: 'paused', value:'warning'},
  {key: 'running', value:'info'},
const $btn = d.getElementById('button');
const $ball = d.getElementById('ball');

$ball.classList.add( statusList[1].key );

$btn.addEventListener('click', () => {
  const status = $btn.getAttribute('data-status') - 0;
  const toggleIndex = !status - 0;
  const now  = statusList[status];
  const next = statusList[toggleIndex];
  $btn.setAttribute('data-status', toggleIndex);
  // reset
  $btn.textContent = now.key;