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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

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

Add External Stylesheets/Pens

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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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You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.

If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.

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Packages

Add Packages

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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About Packages

Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

All packages are different, so refer to their docs for how they work.

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HTML 

              
                <div class="grid">
  <div class="header"><h1>CSS Grid is super cool</h1></div>
   <div class="main-content"><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque tincidunt sagittis metus, ut varius elit fringilla non. Nulla viverra velit sed lectus dignissim, ac sollicitudin tortor feugiat. Mauris pulvinar tempus purus, eu venenatis odio eleifend quis. Fusce placerat libero mauris, nec euismod lorem sagittis eget. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Curabitur auctor rutrum neque, id varius lorem consectetur et. Vivamus convallis ut lorem eget bibendum. Etiam at lacinia metus. </p>
     <p>Fusce nec nisi et massa feugiat euismod et ut enim. Nunc et consequat elit. Phasellus ultricies, erat in dictum eleifend, tellus odio sodales sem, in pulvinar metus dui eu ligula. Integer efficitur convallis neque. Maecenas magna elit, tempor nec elementum vel, tincidunt sit amet ante. In et egestas dolor, eu euismod augue. Nam eu erat in ligula consequat vehicula id eget quam. Vivamus quis dictum turpis.</p></div>
   <div class="side">Side</div>
   <div class="footer">Footer</div>
 
</div>
!

CSS 

              
                *{
  box-sizing:border-box;
}

h1{
  display:none;
}

.grid{
  display: grid;
  grid-template-columns: 1fr 1fr 1fr 1fr;
  grid-template-rows: 100px 400px 50px;
  grid-template-areas:
    "head head head head"
    "main main main side"
    "footer footer footer footer";
  font-family:arial, helvetica, sans-serif;
  grid-row-gap:10px;
  padding:10px;

 
}

.grid p{
  padding:0 20px 0 20px;
  line-height:1.75rem
}

.grid h1{
  text-align:center;
   color:#ffffff;
  font-weight:bold;
  justify-content:center;
  text-align:center;
}

.header{
  grid-area:head;
  background-image: linear-gradient(to bottom right, #254e83 , #c8d9f0);
  background-color:#254e83;
  padding-top:10px;
  
}

.main-content{
  grid-area:main;
  background-color:#175d84;
   padding-top:10px;
  color:#ffffff;
}

.side{
  grid-area:side;
  background-color:#c54c2d;
   padding-top:10px;
  color:#ffffff;
  text-align:center;
  display:flex;
  justify-content:center;
  align-items:center;
  border:3px solid #3d2722;
}
.footer{
  grid-area:footer;
  background-color:#8c897a;
  padding-top:10px;
  color:#ffffff;
  text-align:center;
  align-items:center;
  border:1px solid #000000;
  height:100px;
}
!

JS 

              
                $(document).ready (function(){
  $('h1').fadeIn(5000)
  $(".side").delay(5000).css("background","orange")
});
!
999px

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