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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

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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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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 

              
                <body>
  <h1>Headline: you need to know this!</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Praesent finibus bibendum elit condimentum molestie. Integer dapibus eget enim a consequat. Vestibulum nec rhoncus odio, sed facilisis augue. Nulla congue eleifend nulla, at tincidunt sem auctor et. Vivamus dignissim bibendum quam, quis varius elit tempor ut.</p>
  <h2>First part of the story</h2>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Praesent finibus bibendum elit condimentum molestie. Integer dapibus eget enim a consequat. Vestibulum nec rhoncus odio, sed facilisis augue.</p>
    <h3>This is one aspect</h3>
  <p>Vestibulum nec rhoncus odio, sed facilisis augue. Nulla congue eleifend nulla, at tincidunt sem auctor et. Vivamus dignissim bibendum quam, quis varius elit tempor ut. Nunc consequat, quam et vulputate posuere, metus risus varius orci, eget auctor sapien metus vel.</p>
  <h3>This is another aspect</h3>
  <p>Vivamus dignissim bibendum quam, quis varius elit tempor ut. Nunc consequat, quam et vulputate posuere, metus risus varius orci, eget auctor sapien metus vel.</p>
  <h2>Second part of the story</h2>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Praesent finibus bibendum elit condimentum molestie. Integer dapibus eget enim a consequat. Vestibulum nec rhoncus odio, sed facilisis augue.</p>

</body>
!

CSS 

              
                :root{
  --fs-1: clamp(1.00rem, calc(0.98rem + 0.13vw), 1.13rem);;
  --fs-2: clamp(1.25rem, calc(1.20rem + 0.25vw), 1.50rem);
  --fs-3: clamp(1.56rem, calc(1.48rem + 0.44vw), 2.00rem);
  --fs-4: clamp(1.95rem, calc(1.81rem + 0.71vw), 2.66rem)
}

h1{
  font-size: var(--fs-4);
  line-height: 1.2;
}

h2{
  font-size: var(--fs-3);
  line-height: 1.3;
}

h3{
  font-size: var(--fs-2);
  line-height: 1.4;
}

p{
  font-size: var(--fs-1);
  line-height: 1.5;
}



/*Styling unrelated to the example*/
@import url('https://fonts.googleapis.com/css2?family=Ubuntu&display=swap');

*{
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body, html{
  height: 100%;
}

body{
  padding: var(--fs-3);
  
  color: #222222;
  
  font-family: 'Ubuntu', sans-serif;
  
  /*https://www.magicpattern.design/tools/css-backgrounds*/
  background-color: #DBDBDB;
  opacity: 1;
  background-image:  radial-gradient(#999999 1.4000000000000001px, transparent 1.4000000000000001px), radial-gradient(#999999 1.4000000000000001px, #DBDBDB 1.4000000000000001px);
  background-size: 56px 56px;
  background-position: 0 0,28px 28px;
}

body > * + *{
  margin-top: 1em
}
!

JS
!
999px

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