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CSS

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JavaScript

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HTML 

              
                - let columns = 15
- let rows = 20
- let cells = columns * rows
button.replay
  svg.replay__icon(viewBox="0 0 24 24")
    path(d="M17.65,6.35C16.2,4.9 14.21,4 12,4A8,8 0 0,0 4,12A8,8 0 0,0 12,20C15.73,20 18.84,17.45 19.73,14H17.65C16.83,16.33 14.61,18 12,18A6,6 0 0,1 6,12A6,6 0 0,1 12,6C13.66,6 15.14,6.69 16.22,7.78L13,11H20V4L17.65,6.35Z")
.bear-grid(style=`--cells: ${cells}; --columns: ${columns}; --rows: ${rows}`)
  - for(let b = 1; b < cells + 1; b++)
    .bear-grid__cell(style=`--x: ${(b - 1) % columns}; --y: ${b % columns === 0 ? Math.floor(b / columns) - 1 : Math.floor(b / columns)}; --destinationY: ${Math.floor(Math.random() * 500)}; --destinationX: ${Math.floor(Math.random() * 500)}; --rotation: ${Math.floor(Math.random() * 360)}`)
!

CSS 

              
                *
  box-sizing border-box
  animation  fadeIn .5s

body
  background-color #111
  display flex
  align-items center
  justify-content center
  min-height 100vh

.bear-grid
  --height 320
  --width 240
  display grid
  grid-template-rows repeat(var(--rows), 1fr)
  grid-template-columns repeat(var(--columns), 1fr)
  height calc(var(--height) * 1px)
  transition height .25s, width .25s
  width calc(var(--width) * 1px)

  @media(min-width 768px)
    --height 400
    --width 300

  &--fading .bear-grid__cell
    animation-play-state running
    animation-name driftAway

  &__cell
    --cellWidth calc((calc(var(--width) * -1px)) / var(--columns))
    --cellHeight calc((calc(var(--height) * -1px)) / var(--rows))
    background url(https://jh3y-bear-doesnt-feel-good.netlify.com/dontfeelgoodbear.svg)
    background-size calc(var(--width) * 1px) calc(var(--height) * 1px)
    background-position calc(var(--x) * var(--cellWidth)) calc(var(--y) * var(--cellHeight))
    animation-delay calc(var(--x) * .2s + 1s)
    animation-fill-mode backwards
    animation-duration 4s
    animation-play-state paused
    opacity 0
    transform translate(calc(var(--destinationX) * -1px), calc(var(--destinationY) * -1px)) rotate(calc(var(--rotation) * 1deg)) scale(0)

.replay
  animation fadeIn .25s
  background 0
  border 0
  cursor pointer
  display none
  height 44px
  left 50%
  margin-left -22px
  margin-top -22px
  padding 0
  position fixed
  top 50%
  width 44px
  z-index 2

  &:active
    transform translateY(5%)

  &--show
    display block

  &__icon
    height 44px
    width 44px

    path
      fill #fff

@keyframes fadeIn
  from
    opacity 0

@keyframes driftAway
  from
    transform translate(0, 0) rotate(0deg) scale(1)
    opacity 1
!

JS 

              
                const bearGrid = document.querySelector('.bear-grid')
const bearCells = bearGrid.querySelectorAll('.bear-grid__cell')
const lastCell = bearCells[bearCells.length - 1]
const replay = document.querySelector('.replay')


const imageHasLoaded = (src) => new Promise((resolve, reject) => {
  const img = new Image()
  img.onload = resolve
  img.onerror = reject
  img.src = src
})

const showReset = () => {
  bearGrid.classList.toggle('bear-grid--fading')
  replay.classList.toggle('replay--show')
}

const fade = () => {
  replay.classList.toggle('replay--show')
  bearGrid.classList.toggle('bear-grid--fading')
}


lastCell.addEventListener('animationend', showReset)
replay.addEventListener('click', fade)

imageHasLoaded('https://jh3y-bear-doesnt-feel-good.netlify.com/dontfeelgoodbear.svg')
  .then(() => {
    bearGrid.classList.toggle('bear-grid--fading')
  })
!
999px

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