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CSS

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JavaScript

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HTML 

              
                - 150.times do
  .star
.title 404
.gravestones
  - 3.times do
    .cross
.bottompatch
  - 100.times do
    .patch
.msg
  This page doesn't exist.
.crypt
  .roof
  .body
    .door
.fog
.moon
!

CSS 

              
                @font-face
  font-family: 'stranger'
  src: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/455279/stranger.ttf') format('truetype')

html
  background: linear-gradient(0deg, #050514, #30336b)
  overflow: hidden
  height: 100%
  body
    margin: 0
    
.patch
  position: absolute
  bottom: 0
  height: 10vh
  width: 3vw
  background-color: black
  z-index: 2
  &:nth-child(odd)
    background-color: rgba(0,0,0,0.9)
    z-index: 0
  
.bottompatch
  position: absolute
  background-color: red
  bottom: 0
  left: 0
  
.gravestones
  .cross
    position: absolute
    height: 28vh
    width: 1.8vh
    background-color: black
    bottom: 0
    z-index: 1
    &:after
      content: ""
      position: absolute
      background-color: inherit
      height: 1.8vh
      width: 10vh
      top: 5vh
      left: 50%
      transform: translateX(-50%)
    &:nth-child(1)
      left: 20%
    &:nth-child(2)
      left: 70%
      bottom: -4vh
    &:nth-child(3)
      left: 90%
 

.msg
  display: none
  color: black
  font-size: 6.2vh
  font-family: 'stranger', arial
  position: absolute
  bottom: 14vh
  left: 50%
  transform: translateX(-50%)
  z-index: 2
.crypt
  position: absolute
  bottom: 0
  left: 50%
  transform: translateX(-50%)
  width: 38vh
  height: 40vh
  .roof
    height: 10vh
    width: 100%
    background-color: black
    -webkit-clip-path: polygon(21% 0%, 79% 0%, 100% 100%, 0% 100%)
    clip-path: polygon(21% 0%, 79% 14%, 100% 100%, 0% 100%)
  .body
    width: 86%
    height: 100%
    background-color: black
    margin: -1vh auto 0 auto
    .door
      position: absolute
      bottom: 0
      left: 50%
      transform: translateX(-50%) rotateZ(-3deg)
      width: 20%
      height: 45%
      border-top-right-radius: 100%
      border-top-left-radius: 100%
      background-color: black
    
.fog
  width: 40vh
  height: 20vh
  border-top-right-radius: 100%
  border-top-left-radius: 100%
  background-color: rgba(255,255,255,0.2)
  position: absolute
  bottom: 0
  z-index: 1
  animation-name: fog
  animation-iteration-count: infinite
  animation-duration: 80s
  
.moon
  position: absolute
  top: 8vh
  right: 18vh
  height: 20vh
  width: 20vh
  border-radius: 20vh
  box-shadow: inset -2vh 0 0 #dfe6e9
  transform: rotateZ(32deg)
  
.title
  height: 65vh
  margin: 0
  position: absolute
  left: 49%
  bottom: -90vh
  opacity: 0.1
  transition: filter 3s
  transform: translate(-50%, -50%) rotateZ(-4deg)
  font-family: 'stranger', arial
  font-size: 60vh
  color: #dfe6e9
  z-index: 1
  
.life
  opacity: 1
  transition: opacity 4s
  animation-name: float
  animation-iteration-count: infinite
  animation-duration: 5s
  
  

.star
  height: 1px
  width: 1px
  background-color: white
  position: absolute
  z-index: 0

@keyframes fog 
  0%
    filter: blur(10vh)
    left: -9vw
    transform: rotateZ(19deg)
  50%
    filter: blur(13vh)
    left: 109vw
  100% 
    filter: blur(10vh)
    left: 9vw
    transform: rotateZ(-19deg)
  
@keyframes float
  0%
    top: 45%
  50%
    top: 46%
  100% 
    top: 45%
!

JS 

              
                $(".patch").each((i) => {
  let b = i + 1
  let rX = Math.floor(Math.random() * 50)
  let rY = Math.floor(Math.random() * 100)
  let rH = Math.floor(Math.random() * 10) + 15
  $(".patch:nth-child("+b+")").css({
    left: i-1+"vw",
    height: rH+"vh",
    "-webkit-clip-path": "polygon("+rX+"% "+rX+"%, 0% 100%, 100% 100%)",
    "clip-path": "polygon("+rX+"% "+rX+"%, 0% 100%, 100% 100%)"
  })
})

$(".cross").each((i) => {
  let b = i + 1
  let rR = Math.floor(Math.random() * 15) * Math.cos(Math.PI * Math.round(Math.random()))
  $(".cross:nth-child("+b+")").css({
    "transform": "rotateZ("+rR+"deg)"
  })
})

$(".star").each((i) => {
  $(".star:nth-child("+i+")").css({
    top: Math.random() * $(document).height() - $(document).height()/4,
    left: Math.random() * $(document).width()
  })
})

init = () => {
  $(".crypt").css({
    "transform": "translateX(-50%) rotateZ("+Math.floor(Math.random() * 5) * Math.cos(Math.PI * Math.round(Math.random()))+"deg)"
  })
  $(".title").animate({
    top: "45%"
  }, 5000, () => {
    $(".title").addClass("life")
    $(".msg").fadeIn(1000)
  })
} 
init()
!
999px

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