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HTML

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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Packages

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HTML 

              
                - var fragments = 30;

mixin fragment(n)
  if (n > 0)
    div.fragment(class = "fragment-" + n)
      +fragment(n - 1)
      
div.container(ontouchstart = "")
  div.fragment-cont
    +fragment(fragments)
!

CSS 

              
                // original image size is 1200 x 1703
$w: 320px
$h: $w * 1.41916667
$fragments: 30
$fragmentH: $h / $fragments
$transDur: 0.25s
$cutDelay: 8

.container, .fragment-cont, .fragment
  transform-style: preserve-3d
  -webkit-transform-style: preserve-3d
  transition: transform $transDur

body
  margin: 0
  perspective: 800px
  -webkit-perspective: 800px
  
.container
  width: $w
  height: $h
  margin: auto
  transform: rotateX(45deg) rotateZ(45deg)
  &:hover
    // roll up
    .fragment-cont
      transform: translateY(-$fragmentH) translate3d(0,2px,5px) rotateX(0deg + (360/$fragments*-3))
    .fragment
      transform: translateY($fragmentH) rotateX(0deg + (360/$fragments*3))
      @for $i from 1 through $fragments
        .fragment-#{$i}
          transition-delay: ($transDur/$cutDelay) * ($i - 1)
      
// for containing fragments and moving them to top of global container
.fragment-cont
  transform: translateY(-$fragmentH) rotateX(0deg)
  
.fragment
  // background size has extra 0.75% to hide white edge at right; then in second @for loop, 0.25% of fragment height (0.0025) is added to background position to preserve top dark edge of paper
  background-image: url(https://www.sethkaller.com/images/extras/Constitutionw.png)
  background-size: 100.75% auto
  width: 100%
  height: $fragmentH
  transform-origin: 0% 0%
  -webkit-transform-origin: 0% 0%
  transform: translateY($fragmentH)
  
// roll down
@for $j from 1 through $fragments
  .fragment-#{$fragments - ($j - 1)}
    background-position: 0 (($h * 0.0025) + ($fragmentH * ($fragments - ($j - 1))))
    transition-delay: ($transDur/$cutDelay) * ($j - 1)
!

JS
!
999px

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