Parallax Star background in CSS

index.haml

<link href='https://fonts.googleapis.com/css?family=Lato:300,400,700' rel='stylesheet' type='text/css'>
#stars
#stars2
#stars3
#title
  %span
    PURE CSS
  %br
  %span
    PARALLAX PIXEL STARS

parallax-star-background-in-css.markdown

Parallax Star background in CSS

Using a very simple sass function, and CSS animation keyframes, built parallax scrolling stars in space. The sass function creates a random star field on each load.

SASS function: https://coderwall.com/p/nqxusa by Kushagra Gour @chinchang457

A Pen by Doug A on CodePen.

License.

script.js

/*
Nothing to see here :)
Made by @screenshake
linkedin.com/in/saranshsinha
*/

scripts

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>

style.sass

@import compass


// n is number of stars required
@function multiple-box-shadow ($n) 
  $value: '#{random(2000)}px #{random(2000)}px #FFF'
  @for $i from 2 through $n
    $value: '#{$value} , #{random(2000)}px #{random(2000)}px #FFF'

  @return unquote($value)

$shadows-small:  multiple-box-shadow(700)
$shadows-medium: multiple-box-shadow(200)
$shadows-big:    multiple-box-shadow(100)

html
  height: 100%
  background: radial-gradient(ellipse at bottom, #1B2735 0%, #090A0F 100%)
  overflow: hidden
    
#stars
  width: 1px
  height: 1px
  background: transparent
  box-shadow: $shadows-small
  animation			: animStar 150s linear infinite
    
  &:after
    content: " "
    position: absolute
    top: 2000px
    width: 1px
    height: 1px
    background: transparent
    box-shadow: $shadows-small
    
#stars2
  width: 2px
  height: 2px
  background: transparent
  box-shadow: $shadows-medium
  animation			: animStar 100s linear infinite
    
  &:after
    content: " "
    position: absolute
    top: 2000px
    width: 2px
    height: 2px
    background: transparent
    box-shadow: $shadows-medium
    
#stars3
  width: 3px
  height: 3px
  background: transparent
  box-shadow: $shadows-big
  animation			: animStar 50s linear infinite
    
  &:after
    content: " "
    position: absolute
    top: 2000px
    width: 3px
    height: 3px
    background: transparent
    box-shadow: $shadows-big

#title
  position: absolute
  top: 50%
  left: 0
  right: 0
  
  color: #FFF
  text-align: center
  font-family: 'lato',sans-serif
  font-weight: 300
  font-size: 50px
  letter-spacing: 10px
  
  margin-top: -60px
  padding-left: 10px
  
  span
    background: -webkit-linear-gradient(white, #38495a)
    -webkit-background-clip: text
    -webkit-text-fill-color: transparent
    
@keyframes animStar
  from	
    transform: translateY(0px)
  to		
    transform: translateY(-2000px)
    

from: https://codepen.io/doug444/pen/PobrOrp
from: https://codepen.io/saransh/pen/BKJun