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HTML

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                .my-pens
  .author
  .pens
    ul#pens-list
div(class='wrapper')
  div(class='timer')
    div(id='min')
      - for(var i=1;i>=0;i--)
        span(id='min_'+i)=i
    div(id='colon') :
    div(id='sectens')
      - for(var i=6;i>=0;i--)
        - if(i==6)
          span(id='sectens_'+i)=0
        - else
          span(id='sectens_'+i)=i
    div(id='secones')
      - for(var i=60;i>=0;i--)
        - if(i==60)
          span(id='secones_'+i)=0
        - else
          span(id='secones_'+i)=(i%10)
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Source+Code+Pro:900');

$dark = #ff7e5e
$light = #ff7e5e

html,body
  height: 100%
  padding: 0
  margin: 0
  

  #attribution
    position: fixed
    right: 10px
    bottom: 10px
    color: #ff7e5e
    z-index: 100
    font-weight: bold
    cursor: pointer
    
    a
      color: inherit
      text-decoration: inherit
  
.wrapper
  font-family: 'Source Code Pro', monospace;
  font-weight: 900;
  display: flex
  justify-content: center
  align-items: center
  position: relative
  width: 100%
  height: 100%
  background-color: #FFCF5E
  
.timer
  position: relative
  box-shadow: 0px 50px 0px 100px #FF5E8F;
  
  border: 20px solid $dark
  border-style: none none solid
  border-radius: 5px 5px 0 0
  overflow: hidden
  color: $light
  display: flex
  justify-content: center
  width: 400px
  margin: 0 auto
  font-size: 100px
  
  
  animation: noborder 60s 1, alarm 1s infinite
  animation-delay: 0s, 60s
  animation-fill-mode: forwards
  
  div#min,#sectens,#secones
    text-align: center
    position: relative
    display: flex
    flex-direction: column
    span:not(:first-child) 
      position: absolute
      top: 150px
      left: 0px
  #colon
    position: relative
  #min
    span#min_1
      animation: popout 1s 1
      animation-delay: 0s
      animation-fill-mode: forwards
    span#min_0
      animation: popin 1s 1
      animation-delay: 0s
      animation-fill-mode: forwards
  #sectens
    span#sectens_6
      animation: popout 1s 1
      animation-delay: 0s
      animation-fill-mode: forwards
    for $num in (5..0)
      span#sectens_{$num}
        $delay = (5 - $num) * 10
        $outdelay = ((5 - ($num - 1)) * 10)
        if $num == 0
          animation: popin 1s 1s 1
          animation-delay:  $delay s
        else
          animation: popin 1s 1s 1, popout2 1s 1s 1
          animation-delay:  $delay s,  $outdelay s
        animation-fill-mode:  forwards
  #secones
    span#secones_60
      animation: popout 1s 1
      animation-delay: 0s
      animation-fill-mode: forwards
    for $num in (59..0)
      span#secones_{$num}
        $delay = 59 - $num
        $outdelay = $delay + 1
        if $num == 0
          animation: popin 1s 1
          animation-delay:  $delay s
        else
          animation: popin 1s 1, popout2 1s 1
          animation-delay:  $delay s,  $outdelay s
        animation-fill-mode:  forwards
    
@keyframes popout
  0%
    transform: translateY(0) scale(1)
    opacity: 1
  100%
    transform: translateY(-150px) scale(.8)
    opacity: 0
@keyframes popout2
  0%
    transform: translateY(-150px) scale(1)
    opacity: 1
  100%
    transform: translateY(-300px) scale(.8)
    opacity: 0
@keyframes popin
  0%
    transform: translateY(0) scale(.8)
    opacity: 1
  100%
    transform: translateY(-150px) scale(1)
    opacity: 1
@keyframes alarm
  0%
    transform: rotateZ(0deg)
  10%
    transform: rotateZ(3deg)
  30%
    transform: rotateZ(-3deg)
  45%
    transform: rotateZ(2deg)
  60%
    transform:  rotateZ(-6deg)
  80%
    transform: rotateZ(10deg)
  100%
    transform: rotateZ(0deg)
@keyframes noborder
  from
    border: 5px solid $dark
  to
    border: 5px solid white
!

JS 

              
                //No JS here ;-)
!
999px

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