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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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About the <head>

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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-.

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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

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 

              
                <h2>1. Super Centered</h2>
<div id="super-centered" class="super-centered">
  <p contenteditable>This is super centered</p>
</div>
<h2>2. The Deconstructed Pancake</h2>
<div id="pancake" class="pancake">
  <div>1</div>
  <div>2</div>
  <div>3</div>
</div>
<h2>3. Sidebar Says ... </h2>
<div id="a-sidebar" class="a-sidebar">
  <div>minmax ( 150px, 25% )</div>
  <div>Conetent here.</div>
</div>
<h2>4. Pancake Stack</h2>
<div id="pancake-stack" class="pancake-stack">
  <div>Header</div>
  <div>Content</div>
  <div>Footer</div>
</div>
<h2>5. Holy Grail Layout</h2>
<div id="holy-grail" class="holy-grail">
  <div class="header">Header</div>
  <div class="l-sidebar">Left sidebar</div>
  <div class="content">Main Content</div>
  <div class="r-sidebar">Right sidebar</div>
  <div class="footer">Footer</div>
</div>
<div>
  <p>These codes are retrieved from YouTube Channel <a href="https://www.youtube.com/watch?v=qm0IfG1GyZU">Google Chrome Developers</a></p>
</div>
!

CSS 

              
                .super-centered {
  background: #335522;
  color: #fff;
  display: grid;
  place-items: center;
}

.pancake {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
}

.pancake div {
  height: 50px;
  text-align: center;
  background: #773355;
  color: #fff;
  flex: 1 1 150px;
/*   flex: 0 1 150px; */
  margin: 5px;
}

.a-sidebar {
  display: grid;
  grid-template-columns: minmax( 150px, 25% ) 1fr;
}

.a-sidebar div {
  padding: 16px;
}
.a-sidebar div:first-child {
  background: #227799;
  color: #fff;
}

.a-sidebar div:last-child {
  background: #997722;
  color: #fff;
}

.pancake-stack {
  display: grid;
  grid-template-rows: auto 1fr auto;
}

.pancake-stack div {
  padding: 1em;
}

.pancake-stack div:first-child {
  background: #cc99aa;
}

.pancake-stack div:nth-child(2) {
  background: #99ccaa;
}

.pancake-stack div:last-child {
  background: #aa99cc;
}

.holy-grail {
  display: grid;
  grid-template: auto 1fr auto / auto 1fr auto;
}
.holy-grail div {
  padding: 1em;
}
.holy-grail .header {
  background: #eeccaa;
  grid-column: 1/4;
}

.holy-grail .l-sidebar {
  background: #eeaacc;
}

.holy-grail .content {
  background: #ccaaee;
}

.holy-grail .r-sidebar {
  background: #aaeecc;
}

.holy-grail .footer {
  background: #aaccee;
  grid-column: 1/4;
}
!

JS
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999px

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