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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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HTML 

              
                h1 animation fill mode
ul#stage.animate
  li
    label default style
    .cell
      .c.stop
  li
    label none
    .cell
      .c.none
  li
    label forwards
    .cell
      .c.forwards
  li
    label backwards
    .cell
      .c.backwards
  li
    label both
    .cell
      .c.both

.center
  button#restartBtn.btn.btn-info(type="button", disabled) RESTART
!

CSS 

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

.c
  position: absolute
  left: 50%
  background-color: #E6E9ED
  // animation move 5s ease 1s 1

.animate
  .c
    animation move 5s ease 1s 1
  .stop
    animation-iteration-count: 0
  for key in (none forwards backwards both)
    .{key}
      animation-fill-mode: key

$w = 2em
  
html
  font-size: 100%
h1
  font-size: 2.4rem
  text-align: center
ul
  list-style: none
  margin: 2em auto 2em
  padding: 0
  max-width: 760px
li
  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
  &:first-child
    border-top: 1px solid #AAB2BD
.cell
  position: relative
  flex: 1
  height: $w
label
  font-size: 83%
  white-space: nowrap
  padding-right: .5em
  width: 8em
.c
  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
  .c[data-col=\"{key}\"]
    background-color: value

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

JS 

              
                const d = document;
const $restart = d.getElementById('restartBtn');

setTimeout(() => {
  $restart.removeAttribute('disabled');
}, 6000);

$restart.addEventListener('click', function() {
  const $stage = d.getElementById('stage');
  $stage.classList.remove('animate');
  this.setAttribute('disabled', true);
  setTimeout(() => {
    $stage.classList.add('animate');
    setTimeout(() => {
      this.removeAttribute('disabled');
    }, 6000);
  }, 100);
});
!
999px

Console