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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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About Vendor Prefixing

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <div class='blurImg'>
  <div style="background-image: url('https://d262ilb51hltx0.cloudfront.net/fit/c/1600/1280/gradv/29/81/60/darken/25/1*4ncz3hLxmL8E_bUh-0z62w.jpeg')"></div>
  <div class='blur' style="background-image: url('https://d262ilb51hltx0.cloudfront.net/fit/c/1600/1280/gradv/29/81/40/darken/50/blur/50/1*4ncz3hLxmL8E_bUh-0z62w.jpeg')"></div>
</div>
<header>
  <div>
    <h1>
      Medium
    </h1>
    <p>
      Everyone’s stories and ideas
    </p>
    <a href='https://medium.com/' title='Medium'>Learn more</a>
  </div>
  <nav role='navigation'>
    <ul>
      <li>
        <a class='active' href='#'>Reading List</a>
      </li>
      <li>
        <a href='#'>Bookmarks</a>
      </li>
      <li>
        <a href='#'>Top 100</a>
      </li>
    </ul>
  </nav>
</header>
<div class='container'>
  <div></div>
</div>
!

CSS 

              
                @import "nib"

body
  font-size 14px
  font-family Sans-Serif

*
  box-sizing border-box

a
  text-decoration none

.blurImg
  position relative
  width 100%
  height 440px
  z-index -1
  top 0
  left 0
  & > div
    position fixed
    width 100%
    height 440px
    background-repeat no-repeat
    background-size cover
    background-position center center

.blur
  opacity 0

header
  z-index 1
  position absolute
  top 0
  width 100%
  padding 0px 20px
  & > div
    max-width 600px
    margin 0 auto
    padding-top 150px
    height 380px
    text-align center
    color White
    a
      font-size 0.8em
      letter-spacing 0.08em
      color rgba(255,255,255,0.85)
      line-height 30px
      padding 7px 14px
      border 1px solid rgba(255,255,255,0.3)
      border-radius 2em
      transition all 0.3s ease
      &:hover
        background white
        color Gray
  p
    font-size 1.5em
    margin-bottom 0.7em
    font-family Times New Roman

h1
  font-weight 800
  font-size 3.4em
  margin-bottom 0.2em

nav
  max-width 600px
  margin 0 auto
  height 60px
  border-top 1px rgba(255,255,255,0.35) solid
  ul
    li
      display inline-block
      margin-right 20px
      a
        font-weight 800
        font-size 11px
        text-transform uppercase
        letter-spacing .2em
        color rgba(255,255,255,0.5)
        transition color 0.3s linear
        line-height 60px
        display block
        &.active
          box-shadow 0px -1px 0px white

nav ul li a.active, nav ul li a:hover
  color white

.container
  height 1300px
  background white
  z-index 1
  padding 0px 20px
  div
    max-width 600px
    margin 0 auto
    padding-top 40px
!

JS 

              
                #Image Credit - https://medium.com/

#https://github.com/andreasstorm

$(window).scroll ->
  oVal = ($(window).scrollTop() / 240)
  $(".blur").css "opacity", oVal
!
999px

Console