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About CSS Base

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About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient. For instance, CoffeeScript can help prevent easy-to-make mistakes and offer a cleaner syntax and Babel can bring ECMAScript 6 features to browsers that only support ECMAScript 5.

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You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

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HTML

            
              .button__wrap
  button.button(style=`--hue: ${Math.random() * 360}`) Show me attention
  .button__shadow
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CSS

            
              body
  min-height 100vh
  display flex
  align-items center
  justify-content center
  
.button
  --y -25
  --x 0
  --rotation 0
  --speed 2
  --txt "Show me attention"
  --padding 1rem 1.25rem
  cursor pointer
  padding var(--padding)
  color transparent
  font-weight bold
  font-size 1.25rem
  transition background .1s ease
  background 'hsl(%s, 100%, 50%)' % (var(--hue))
  outline-color 'hsl(%s, 100%, 80%)' % (var(--hue))
  animation-name flow-and-shake
  animation-duration calc(var(--speed) * 1s)
  animation-iteration-count infinite
  animation-timing-function ease-in-out
  
  &:after
    content var(--txt)
    position absolute
    top 0
    right 0
    bottom 0
    left 0
    padding var(--padding)
    color #fff
  
  &:hover
    background 'hsl(%s, 100%, 40%)' % (var(--hue))
    --speed .1
    --rotation -1
    --y -1
    --x 1
    --txt "Click me!"
      
  &:active
    --speed 4
    --x 0
    --y 5
    --rotation 0
    --txt "Ahhhh..."
    background 'hsl(%s, 100%, 30%)' % (var(--hue))

    
  &__wrap
    position relative
    
  &__shadow
    position absolute
    border-radius 100%
    bottom 0
    left 0
    right 0
    height 4px
    background hsl(0, 10%, 65%)
    animation shadow 2s infinite ease-in-out
    z-index -1
  

@keyframes shadow
  0%, 100%
    transform scaleX(1)
    opacity 1
  50%
    opacity .2
    transform scaleX(.25)

@keyframes flow-and-shake
  0%, 100%
    transform translate(calc(var(--x) * -1%), 0) rotate(calc(var(--rotation) * -1deg))
  50%
    transform translate(calc(var(--x) * 1%), calc(var(--y) * 1%)) rotate(calc(var(--rotation) * 1deg))
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JS
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