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HTML

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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

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About Vendor Prefixing

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JavaScript

About JavaScript Preprocessors

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 

              
                <div id="fan"></div>
!

CSS 

              
                // #divtober 01: Fan
// a.singlediv.com/divtober2021

black(alpha)
  rgba(0,0,0,alpha)

white(alpha)
  rgba(255,255,255,alpha)

body
  min-height: 300px
  height: 100vh
  position: relative
  background-color: #eee
  background-image: linear-gradient(to top, #ddd calc(50% - 6.5em), white(0) calc(50% - 6.5em))
  text-align: center

div
  position: absolute
  left: 50%
  top: 50%

  &:before,
  &:after
    display: block
    content: ''
    position: absolute

#fan
  width: 14em
  height: 15em
  margin-left: -(@width/2)
  margin-top: -6em
  background-repeat: no-repeat
  background-image: linear-gradient(to bottom, #ccc .3em, #443e48 .3em),
                    linear-gradient(to bottom, #222 10em, transparent 10em),
                    radial-gradient(ellipse at center, black(.1) 20%, black(.0) 50%)
  background-size: 93% 8.1em, 100% 100%, 18em 1.5em
  background-position: 50% .6em, 0 0, left 50% bottom 0
  border-radius: 5px
  animation: floating 1500ms infinite ease-in-out

  &:after
    width: 18em
    height: .7em
    left: -2em
    top: 9.3em
    background-color: #ccc
    background-repeat: no-repeat
    background-image: linear-gradient(to top, #888 20%, black(0) 40%),
                      linear-gradient(to right, black(.3),
                                                black(0) 1%,
                                                black(0) 1.2%,
                                                black(.3) 2.5%,
                                                black(0) 5%),
                      linear-gradient(to left, black(.3),
                                                black(0) 1%,
                                                black(0) 1.2%,
                                                black(.3) 2.5%,
                                                black(0) 5%),
                      linear-gradient(35deg, black(0) 30%,
                                             black(.3) 40%,
                                             black(0) 70%),
                      linear-gradient(-35deg, black(0) 30%,
                                             black(.3) 40%,
                                             black(0) 70%),
                      linear-gradient(to top, black(.15) 20%, black(0) 30%)
    background-size: 100% 100%, 100% 100%, 100% 100%,
                     .5em .3em, .5em .3em, 1.8em .3em
    background-position: 0 0, 0 0, 0 0,
                         44% 0, 56% 0, 50% 0
    border-radius: 1px
    border-bottom-left-radius: 1em .3em
    border-bottom-right-radius: 1em .3em

  &:before
    content: '☠️☠️☠️'
    box-sizing: border-box
    width: 4em
    height: 11em
    margin-left: -(@width/2)
    padding-top: 4.5em
    left: 50%
    top: 0
    background-image: linear-gradient(to right, #444 20%, #333 50%, black(0) 50%),
                      linear-gradient(to right, #aaa, #ccc, #aaa)
    background-repeat: repeat-x, no-repeat
    background-size: 100% .3em, .3em 1em
    background-position: 0 100%, 50% 100%
    animation: fan 60ms infinite linear

@keyframes fan
  0
    background-position: 0 100%, 50% 100%
  100%
    background-position: 4em 100%, 50% 100%

@keyframes floating
  0, 100%
    transform: translate(0,0)
    background-size: 93% 8.1em, 100% 100%, 18em 1.5em
    background-position: 50% .6em, 0 0, left 50% bottom 0
  50%
    transform: translate(0,.5em)
    background-size: 93% 8.1em, 100% 100%, 21em 1.8em
    background-position: 50% .6em, 0 0, left 50% bottom .5em
!

JS 

              
                // @lynnandtonic
// a.singlediv.com
!
999px

Console