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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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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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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.

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HTML 

              
                <body>
  <main>
    <h1>Hello world</h1>
    <p class="introduction">
      Spencer welcomes you to the amazing world of
      <span class="topic">web programming</span>.
    </p>
    <dialog id= query> 
    <p>Do you want nachos?<p>
      <form method="dialog">
        <button>OK</button>
      </form>
    </dialog>
    <iframe width=500 height=300 src="https://www.youtube.com/embed/Yw6u6YkTgQ4"></iframe>
    <p class="speech">
      Hello, world<br/> Programmed to work and not to feel<br/>
      Not even sure that this is real<br/>
      Hello, world</p>
    <p>Find my voice <br/>Although, it sounds like bits and bytes<br/>
      My circuitry is filled with lights<br/> Hello, world</p>
    <p> Oh, will I find a love<br/> Or a power plug?<br/>
      Oh, digitally isolated<br/>Oh, creator, please don't leave me waiting</p>
    <p>Hello, world <br/>Programmed to work and not to feel<br/>
      Not even sure that this is real<br/>Hello, world</p>
    <img src="https://media2.giphy.com/media/wCykTNtEJonzlUZAra/200w.webp?cid=ecf05e47c10x6qf9i8c62knc3log03bfpouipgv8mvjcq7iz&rid=200w.webp&ct=g" alt="dance monkey"/>
    <p class="assignment"><a href="https://youtu.be/t7bwZbqPv0I?t=402" alt="epic mariokart music">What I'm currently listening to.</a></p>
  </main>
</body>
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CSS
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JS
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