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HTML

              
                <!-- Bootstrap v5 "Blog" Demo -->
<!-- https://getbootstrap.com/docs/5.1/examples/ -->
<div class="container">
	<header class="blog-header py-3">
		<div class="row flex-nowrap justify-content-between align-items-center">
			<div class="col-4 pt-1">
				<a class="link-secondary" href="#">Subscribe</a>
			</div>
			<div class="col-4 text-center">
				<a class="blog-header-logo text-dark" href="#">Example</a>
			</div>
			<div class="col-4 d-flex justify-content-end align-items-center">
				<a class="link-secondary" href="#" aria-label="Search">
					<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" class="mx-3" role="img" viewBox="0 0 24 24">
						<title>Search</title>
						<circle cx="10.5" cy="10.5" r="7.5" />
						<path d="M21 21l-5.2-5.2" />
					</svg>
				</a>
				<a class="btn btn-sm btn-outline-secondary" href="#">Sign up</a>
			</div>
		</div>
	</header>

	<div class="nav-scroller py-1 mb-2">
		<nav class="nav d-flex justify-content-between">
			<a class="p-2 link-secondary" href="#">World</a>
			<a class="p-2 link-secondary" href="#">U.S.</a>
			<a class="p-2 link-secondary" href="#">Technology</a>
			<a class="p-2 link-secondary" href="#">Design</a>
			<a class="p-2 link-secondary" href="#">Culture</a>
			<a class="p-2 link-secondary" href="#">Business</a>
			<a class="p-2 link-secondary" href="#">Politics</a>
			<a class="p-2 link-secondary" href="#">Opinion</a>
			<a class="p-2 link-secondary" href="#">Science</a>
			<a class="p-2 link-secondary" href="#">Health</a>
			<a class="p-2 link-secondary" href="#">Style</a>
			<a class="p-2 link-secondary" href="#">Travel</a>
		</nav>
	</div>
</div>

<main class="container">
	<div id="hero" class="p-4 p-md-5 mb-4 text-white rounded bg-dark">
		<div class="col-md-6 px-0">
			<h1 class="display-4 fst-italic">This is a page that uses Bootstrap.</h1>
			<p class="lead my-3">Multiple lines of text that form the lede, informing new readers quickly and efficiently about what’s most interesting in this post’s contents.</p>
			<p class="lead mb-0"><a href="#" class="text-white fw-bold">Continue reading...</a></p>
		</div>
	</div>

	<div class="row mb-2">
		<div class="col-md-6">
			<div class="row g-0 border rounded overflow-hidden flex-md-row mb-4 shadow-sm h-md-250 position-relative">
				<div class="col p-4 d-flex flex-column position-static">
					<strong class="d-inline-block mb-2 text-primary">World</strong>
					<h3 class="mb-0">Featured post</h3>
					<div class="mb-1 text-muted">Nov 12</div>
					<p class="card-text mb-auto">This is a wider card with supporting text below as a natural lead-in to additional content.</p>
					<a href="#" class="stretched-link">Continue reading</a>
				</div>
				<div class="col-auto d-none d-lg-block">
					<svg class="bd-placeholder-img" width="200" height="250" xmlns="http://www.w3.org/2000/svg" role="img" aria-label="Placeholder: Thumbnail" preserveAspectRatio="xMidYMid slice" focusable="false">
						<title>Placeholder</title>
						<rect width="100%" height="100%" fill="#55595c" /><text x="50%" y="50%" fill="#eceeef" dy=".3em">Thumbnail</text>
					</svg>

				</div>
			</div>
		</div>
		<div class="col-md-6">
			<div class="row g-0 border rounded overflow-hidden flex-md-row mb-4 shadow-sm h-md-250 position-relative">
				<div class="col p-4 d-flex flex-column position-static">
					<strong class="d-inline-block mb-2 text-success">Design</strong>
					<h3 class="mb-0">Post title</h3>
					<div class="mb-1 text-muted">Nov 11</div>
					<p class="mb-auto">This is a wider card with supporting text below as a natural lead-in to additional content.</p>
					<a href="#" class="stretched-link">Continue reading</a>
				</div>
				<div class="col-auto d-none d-lg-block">
					<svg class="bd-placeholder-img" width="200" height="250" xmlns="http://www.w3.org/2000/svg" role="img" aria-label="Placeholder: Thumbnail" preserveAspectRatio="xMidYMid slice" focusable="false">
						<title>Placeholder</title>
						<rect width="100%" height="100%" fill="#55595c" /><text x="50%" y="50%" fill="#eceeef" dy=".3em">Thumbnail</text>
					</svg>

				</div>
			</div>
		</div>
	</div>

	<div class="row g-5">
		<div class="col-md-8">
			<h3 class="pb-4 mb-4 fst-italic border-bottom">
				From the Firehose
			</h3>

			<article class="blog-post">
				<h2 class="blog-post-title">Sample blog post</h2>
				<p class="blog-post-meta">January 1, 2021 by <a href="#">Mark</a></p>

				<p>This blog post shows a few different types of content that’s supported and styled with Bootstrap. Basic typography, lists, tables, images, code, and more are all supported as expected.</p>
				<hr>
				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<h2>Blockquotes</h2>
				<p>This is an example blockquote in action:</p>
				<blockquote class="blockquote">
					<p>Quoted text goes here.</p>
				</blockquote>
				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<h3>Example lists</h3>
				<p>This is some additional paragraph placeholder content. It's a slightly shorter version of the other highly repetitive body text used throughout. This is an example unordered list:</p>
				<ul>
					<li>First list item</li>
					<li>Second list item with a longer description</li>
					<li>Third list item to close it out</li>
				</ul>
				<p>And this is an ordered list:</p>
				<ol>
					<li>First list item</li>
					<li>Second list item with a longer description</li>
					<li>Third list item to close it out</li>
				</ol>
				<p>And this is a definition list:</p>
				<dl>
					<dt>HyperText Markup Language (HTML)</dt>
					<dd>The language used to describe and define the content of a Web page</dd>
					<dt>Cascading Style Sheets (CSS)</dt>
					<dd>Used to describe the appearance of Web content</dd>
					<dt>JavaScript (JS)</dt>
					<dd>The programming language used to build advanced Web sites and applications</dd>
				</dl>
				<h2>Inline HTML elements</h2>
				<p>HTML defines a long list of available inline tags, a complete list of which can be found on the <a href="https://developer.mozilla.org/en-US/docs/Web/HTML/Element">Mozilla Developer Network</a>.</p>
				<ul>
					<li><strong>To bold text</strong>, use <code class="language-plaintext highlighter-rouge">&lt;strong&gt;</code>.</li>
					<li><em>To italicize text</em>, use <code class="language-plaintext highlighter-rouge">&lt;em&gt;</code>.</li>
					<li>Abbreviations, like <abbr title="HyperText Markup Langage">HTML</abbr> should use <code class="language-plaintext highlighter-rouge">&lt;abbr&gt;</code>, with an optional <code class="language-plaintext highlighter-rouge">title</code> attribute for the full phrase.</li>
					<li>Citations, like <cite>— Mark Otto</cite>, should use <code class="language-plaintext highlighter-rouge">&lt;cite&gt;</code>.</li>
					<li><del>Deleted</del> text should use <code class="language-plaintext highlighter-rouge">&lt;del&gt;</code> and <ins>inserted</ins> text should use <code class="language-plaintext highlighter-rouge">&lt;ins&gt;</code>.</li>
					<li>Superscript <sup>text</sup> uses <code class="language-plaintext highlighter-rouge">&lt;sup&gt;</code> and subscript <sub>text</sub> uses <code class="language-plaintext highlighter-rouge">&lt;sub&gt;</code>.</li>
				</ul>
				<p>Most of these elements are styled by browsers with few modifications on our part.</p>
				<h2>Heading</h2>
				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<h3>Sub-heading</h3>
				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<pre><code>Example code block</code></pre>
				<p>This is some additional paragraph placeholder content. It's a slightly shorter version of the other highly repetitive body text used throughout.</p>
			</article>

			<article class="blog-post">
				<h2 class="blog-post-title">Another blog post</h2>
				<p class="blog-post-meta">December 23, 2020 by <a href="#">Jacob</a></p>

				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<blockquote>
					<p>Longer quote goes here, maybe with some <strong>emphasized text</strong> in the middle of it.</p>
				</blockquote>
				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<h3>Example table</h3>
				<p>And don't forget about tables in these posts:</p>
				<table class="table">
					<thead>
						<tr>
							<th>Name</th>
							<th>Upvotes</th>
							<th>Downvotes</th>
						</tr>
					</thead>
					<tbody>
						<tr>
							<td>Alice</td>
							<td>10</td>
							<td>11</td>
						</tr>
						<tr>
							<td>Bob</td>
							<td>4</td>
							<td>3</td>
						</tr>
						<tr>
							<td>Charlie</td>
							<td>7</td>
							<td>9</td>
						</tr>
					</tbody>
					<tfoot>
						<tr>
							<td>Totals</td>
							<td>21</td>
							<td>23</td>
						</tr>
					</tfoot>
				</table>

				<p>This is some additional paragraph placeholder content. It's a slightly shorter version of the other highly repetitive body text used throughout.</p>
			</article>

			<article class="blog-post">
				<h2 class="blog-post-title">New feature</h2>
				<p class="blog-post-meta">December 14, 2020 by <a href="#">Chris</a></p>

				<p>This is some additional paragraph placeholder content. It has been written to fill the available space and show how a longer snippet of text affects the surrounding content. We'll repeat it often to keep the demonstration flowing, so be on the lookout for this exact same string of text.</p>
				<ul>
					<li>First list item</li>
					<li>Second list item with a longer description</li>
					<li>Third list item to close it out</li>
				</ul>
				<p>This is some additional paragraph placeholder content. It's a slightly shorter version of the other highly repetitive body text used throughout.</p>
			</article>

			<nav class="blog-pagination" aria-label="Pagination">
				<a class="btn btn-outline-primary" href="#">Older</a>
				<a class="btn btn-outline-secondary disabled">Newer</a>
			</nav>

		</div>

		<div class="col-md-4">
			<div class="position-sticky" style="top: 2rem;">
				<div class="p-4 mb-3 bg-light rounded">
					<h4 class="fst-italic">About</h4>
					<p class="mb-0">Customize this section to tell your visitors a little bit about your publication, writers, content, or something else entirely. Totally up to you.</p>
				</div>

				<div class="p-4">
					<h4 class="fst-italic">Archives</h4>
					<ol class="list-unstyled mb-0">
						<li><a href="#">March 2021</a></li>
						<li><a href="#">February 2021</a></li>
						<li><a href="#">January 2021</a></li>
						<li><a href="#">December 2020</a></li>
						<li><a href="#">November 2020</a></li>
						<li><a href="#">October 2020</a></li>
						<li><a href="#">September 2020</a></li>
						<li><a href="#">August 2020</a></li>
						<li><a href="#">July 2020</a></li>
						<li><a href="#">June 2020</a></li>
						<li><a href="#">May 2020</a></li>
						<li><a href="#">April 2020</a></li>
					</ol>
				</div>

				<div class="p-4">
					<h4 class="fst-italic">Elsewhere</h4>
					<ol class="list-unstyled">
						<li><a href="#">GitHub</a></li>
						<li><a href="#">Twitter</a></li>
						<li><a href="#">Facebook</a></li>
					</ol>
				</div>
			</div>
		</div>
	</div>

</main>

<footer class="blog-footer">
	<p>Blog template built for <a href="https://getbootstrap.com/">Bootstrap</a> by <a href="https://twitter.com/mdo">@mdo</a>.</p>
	<p>
		<a href="#">Back to top</a>
	</p>
</footer>
              
            
!

CSS

              
                /* Bootstrap v5 "Blog" Demo */
/* https://getbootstrap.com/docs/5.1/examples/ */
.bd-placeholder-img {
	font-size: 1.125rem;
	text-anchor: middle;
	-webkit-user-select: none;
	-moz-user-select: none;
	user-select: none;
}

@media (min-width: 768px) {
	.bd-placeholder-img-lg {
		font-size: 3.5rem;
	}
}
              
            
!

JS

              
                // Make a new template.
const template = document.createElement('template');
template.innerHTML = `
	<style>
		/* Reset all inheritable properties. */
		/* https://gist.github.com/tannerhodges/4c2b727edea02cae9b16a4ebf15d5fe3 */
		:host {
			border-collapse: separate;
			border-spacing: 0;
			caption-side: top;
			color: canvastext;
			cursor: auto;
			direction: ltr;
			empty-cells: show;
			font: normal normal normal normal medium normal sans-serif;
			letter-spacing: normal;
			line-height: normal;
			list-style: disc outside none;
			orphans: 2;
			quotes: auto;
			speak: auto;
			text-align: start;
			text-indent: 0;
			text-transform: none;
			visibility: visible;
			white-space: normal;
			widows: 2;
			word-spacing: normal;
		}
		
		/* Custom styles. */
		div {
			margin-block: 2rem;
			padding: 1.5rem;
			border: 1px solid black;
			border-radius: 4px;
			background: yellow;
		}
		
		h2 {
			margin-block-start: 0;
		}
	</style>
	<!-- And your HTML! -->
	<div>
		<h2>Example Web Component</h2>
		<!-- Did I mention you can render slots too? -->
		<slot></slot>
	</div>
`;

class XComponent extends HTMLElement {
	constructor() {
		super();
		
		// Shadow DOM also encapsulates CSS (and other cool features).
		// attachShadow() creates a shadow root instance.
		this.attachShadow({ mode: 'open' });
		
		// Append our template to the Shadow DOM...
		this.shadowRoot.appendChild(template.content.cloneNode(true));
	}
}

// Define our new Web Component as a custom element.
customElements.define('x-component', XComponent);

// DEMO: Add an instance of our component after the hero...
const hero = document.querySelector('#hero');

hero.insertAdjacentHTML('afterend', `
	<x-component>Hello! This component's styles are completely separate from the rest of the page.</x-component>
`);

              
            
!
999px

Console