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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

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CSS

About CSS Preprocessors

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.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

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

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Babel includes JSX processing.

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HTML 

              
                <h1>Fun with line-height</h1>

<section> 
  <h2>Funsville</h2>
  <p>When you know the line-height, you can make a linear-grdient that has hard color stops in between each line of text. Gaperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio.</p>
</section>

<section>
  <h2>Emphasize Start</h2>
  <p>It's easiest when the background starts on top of the text like in this case, consectetur adipisicing elit. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio</p>
</section>

<section>
  <h2>Fade Out Bottom</h2>
  <p>But we can also make it work for the bottom of text (depite its length) by using calc() in the gradients, substracting it from the elements full height. Sit amet, consectetur adipisicing elit. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio</p>
</section>

<section> 
  <h2>Lines</h2>
  <p>There are plenty of little things that can screw this up, but if you're careful, you can create a 1px gradient that repeats at the current line-height so that it's between lines of text no matter what. I first saw Lea Verou do this. Lorem ipsum dolor sit amet, consectetur adipisicing elit. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio.</p>
</section>

<section>
  <h2>Ticks</h2>
  <p>You can set the background-size of an image to match the line-height, so that it's always the same size of a line. Perferendis Lorem ipsum dolor sit amet, consectetur adipisicing elit. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio. Corrupti cupiditate, aperiam nemo saepe sunt enim, perferendis aut numquam est doloremque tempora molestias in vero? Eius animi odit earum, fugit optio</p>
</section>
!

CSS 

              
                $lh: 1.4em;

body {
  font-size: 1em;
  line-height: $lh;
}

h1 {
  background: #333;
  margin: 0;
  padding: 5% 20%;
  text-transform: uppercase;
  color: #eee;
  font-size: 2em;
}

section {
  padding: 5% 20%;
  h2 {
    margin: 0 0 $lh 0;
    color: white;
    text-transform: uppercase;
    letter-spacing: 0.5em;
    font-size: 1em;
  }
  p {
    margin: 0 0 1em 0;
  }
  @media (max-width: 400px) {
    padding: 10%;
  }
}

section:nth-of-type(1) {
  background: #082838;
  @supports (-webkit-background-clip: text) {
    p {
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-image: linear-gradient(
        to bottom,
        #9588DD,
        #9588DD $lh,
        #DD88C8 $lh,
        #DD88C8 $lh*2,
        #D3DD88 $lh*2,
        #D3DD88 $lh*3,
        #88B0DD $lh*3,
        #88B0DD);
    }
  }
}

section:nth-of-type(2) {
  background: #111;
  p {
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-image: linear-gradient(
      to bottom,
      rgba(white, 0.8),
      rgba(white, 0.8) $lh,
      rgba(white, 0.6) $lh,
      rgba(white, 0.6) $lh*2,
      rgba(white, 0.4) $lh*2,
      rgba(white, 0.4) $lh*3,
      rgba(white, 0.2) $lh*3,
      rgba(white, 0.2));
  }
}

section:nth-of-type(3) {
  background: #333;
  p {
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-image: linear-gradient(
      to bottom,
      rgba(white, 0.8),
      rgba(white, 0.8) calc(100% - 66px),
      rgba(white, 0.6) calc(100% - 66px),
      rgba(white, 0.6) calc(100% - 44px),
      rgba(white, 0.4) calc(100% - 44px),
      rgba(white, 0.4) calc(100% - 22px),
      rgba(white, 0.2) calc(100% - 22px),
      rgba(white, 0.2));
  }
}

section:nth-of-type(4) {
  padding: $lh*2;
  background: #082838;
  background-image: repeating-linear-gradient(
    to bottom,
    rgba(white, 0)   0,
    rgba(white, 0) $lh/1em*16px-1,
    rgba(white, 0.1) $lh/1em*16px-1,
    rgba(white, 0.1) $lh/1em*16px
  );
  p {
    opacity: 0.75;
    color: white;
  }
}

section:nth-of-type(5) {
  background: #111;
  p {
    color: #999;
    background-image: url("https://s3-us-west-2.amazonaws.com/s.cdpn.io/3/tick.svg");
    padding-left: $lh*2;
    background-size: $lh $lh;
    background-repeat: repeat-y;
  }
}
!

JS
!
999px

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