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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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Insecure Resource

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CSS

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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

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <h1><i>Star Trek: Discovery</i></h1>
<hgroup>
	<h2 id="s1">Season 1</h2>
	<button>
		<span aria-hidden="true">🔗</span>
		<span class="visually-hidden">copy to clipboard</span>
	</button>
</hgroup>
<hgroup>
	<h3 id="s1c1">Chapter 1</h3>
	<button>
		<span aria-hidden="true">🔗</span>
		<span class="visually-hidden">copy to clipboard</span>
	</button>
</hgroup>
<p>The series begins around ten years before the events of <i>Star Trek: The Original Series</i>, when Commander Michael Burnham’s actions start a war between the United Federation of Planets and the Klingon Empire. She is court-martialed, stripped of rank, and reassigned to the USS <i>Discovery</i>, which has a unique means of propulsion called the “Spore Drive”.</p>
<hgroup>
	<h3 id="s1c2">Chapter 2</h3>
	<button>
		<span aria-hidden="true">🔗</span>
		<span class="visually-hidden">copy to clipboard</span>
	</button>
</hgroup>
<p>After an adventure in the Mirror Universe, <i>Discovery</i> helps end the Klingon war.</p>
<hgroup>
	<h2 id="s2">Season 2</h2>
	<button>
		<span aria-hidden="true">🔗</span>
		<span class="visually-hidden">copy to clipboard</span>
	</button>
</hgroup>
<p>In the second season they investigate seven mysterious signals and a strange figure known as the “Red Angel”, and fight off a rogue artificial intelligence. This conflict ends with the <i>Discovery</i> traveling to the 32nd century, more than 900 years into their future.</p>
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CSS 

              
                body {
	font: 1em/1.4 Lato, sans-serif;
	max-width: 68ch;
}

hgroup {
	display: flex;
	align-items: end;
	gap: 1em;
}

h1, h2, h3, h4, h5, h6 {
	margin-block: 1em 0;
}

.visually-hidden:not(:focus):not(:active) {
	clip: rect(0 0 0 0);
	clip-path: inset(50%);
	height: 1px;
	overflow: hidden;
	position: absolute;
	white-space: nowrap;
	width: 1px;
}
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JS 

              
                document.body.addEventListener('click', (event) => {
	const buttonElement = event.target.closest('button');
	
	if (buttonElement) {
		const hash = buttonElement.closest('hgroup')?.querySelector('h1, h2, h3, h4, h5, h6')?.id;		
		writeClipboardText(`${window.location.protocol}${window.location.host}${window.location.pathname}${window.location.search}#${hash}`);
	}
});

async function writeClipboardText(text) {
	try {
		await navigator.clipboard.writeText(text);
	}
	catch (error) {
		console.error(error.message);
	}
}
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999px

Console