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CSS

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JavaScript

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HTML 

              
                .error-page
  div
    //h1(data-h1='400') 400
    //p(data-p='BAD REQUEST') BAD REQUEST
    //h1(data-h1='401') 401
    //p(data-p='UNAUTHORIZED') UNAUTHORIZED
    //h1(data-h1='403') 403
    //p(data-p='FORBIDDEN') FORBIDDEN
    h1(data-h1="404") 404
    p(data-p="NOT FOUND") NOT FOUND
    //h1(data-h1='500') 500
    //p(data-p='SERVER ERROR') SERVER ERROR

#particles-js

//a(href="#").back GO BACK
!

CSS 

              
                html, body
  height: 100%
  overflow: hidden

.error-page
  display: flex
  align-items: center
  justify-content: center
  text-align: center
  height: 100%
  font-family: Arial,"Helvetica Neue",Helvetica,sans-serif
  
  h1
    font-size: 30vh
    font-weight: bold
    position: relative
    margin: -8vh 0 0
    padding: 0
    
    &:after
      content: attr(data-h1)
      position: absolute
      top: 0
      left: 0
      right: 0
      color: transparent
      /* webkit only for graceful degradation to IE */
      background: -webkit-repeating-linear-gradient(-45deg, #71b7e6, #69a6ce, #b98acc, #ee8176, #b98acc, #69a6ce, #9b59b6)
      -webkit-background-clip: text
      -webkit-text-fill-color: transparent
      background-size: 400%
      text-shadow: 1px 1px 2px transparentize(#fff, .75)
      animation: animateTextBackground 10s ease-in-out infinite
    
    + p
      color: #d6d6d6
      font-size: 8vh
      font-weight: bold
      line-height: 10vh
      max-width: 600px
      position: relative
      
      &:after
        content: attr(data-p)
        position: absolute
        top: 0
        left: 0
        right: 0
        color: transparent
        text-shadow: 1px 1px 2px transparentize(#fff, .5)
        -webkit-background-clip: text
        -moz-background-clip: text
        background-clip: text

#particles-js
  position: fixed
  top: 0
  right: 0
  bottom: 0
  left: 0

@keyframes animateTextBackground
  0%
    background-position: 0 0
  
  25%
    background-position: 100% 0
  
  50%
    background-position: 100% 100%
  
  75%
    background-position: 0 100%
  
  100%
    background-position: 0 0

@media (max-width: 767px)
  
  .error-page h1
    font-size: 32vw
    
    + p
      font-size: 8vw
      line-height: 10vw
      max-width: 70vw
      
a.back
  position: fixed
  right: 40px
  bottom: 40px
  background: -webkit-repeating-linear-gradient(-45deg, #71b7e6, #69a6ce, #b98acc, #ee8176)
  border-radius: 5px
  box-shadow: 0 2px 10px rgba(0,0,0,0.2)
  color: #fff
  font-size: 16px
  font-weight: bold
  line-height: 24px
  padding: 15px 30px
  text-decoration: none
  transition: 0.25s all ease-in-out
  &:hover
    box-shadow: 0 4px 20px rgba(0,0,0,0.4)
!

JS 

              
                particlesJS("particles-js", {
  "particles": {
    "number": {
      "value": 5,
      "density": {
        "enable": true,
        "value_area": 800
      }
    },
    "color": {
      "value": "#fcfcfc"
    },
    "shape": {
      "type": "circle",
    },
    "opacity": {
      "value": 0.5,
      "random": true,
      "anim": {
        "enable": false,
        "speed": 1,
        "opacity_min": 0.2,
        "sync": false
      }
    },
    "size": {
      "value": 140,
      "random": false,
      "anim": {
        "enable": true,
        "speed": 10,
        "size_min": 40,
        "sync": false
      }
    },
    "line_linked": {
      "enable": false,
    },
    "move": {
      "enable": true,
      "speed": 8,
      "direction": "none",
      "random": false,
      "straight": false,
      "out_mode": "out",
      "bounce": false,
      "attract": {
        "enable": false,
        "rotateX": 600,
        "rotateY": 1200
      }
    }
  },
    "interactivity": {
    "detect_on": "canvas",
    "events": {
      "onhover": {
        "enable": false
      },
      "onclick": {
        "enable": false
      },
      "resize": true
    }
  },
  "retina_detect": true
});
!
999px

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