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HTML 

              
                <h1>All About Cheese</h1>
<p class="meta">From the article "Finding Heading Level Errors", use this page to test the <a href="https://khan.github.io/tota11y/">tota11y tool</a> (bottom left corner, with the eye-glasses icon) for finding problems with this page's use of headings. There is <a href="#answers">one error</a> from the list of <a href="https://mrwweb.com/common-heading-mistakes/">Common Heading Mistakes</a> on this page. The answer is at the <a href="#answer">bottom</a>.

<h3>Types of Cheese</h3>
<p>This is nonsense paragraph content. This is nonsense paragraph content.</p>
<ul>
	<li>This is nonsense paragraph content.</li>
	<li>This is nonsense paragraph content.</li>
	<li>This is nonsense paragraph content. This is nonsense paragraph content.</li>
	<li>This is nonsense.</li>
</ul>
<h4>Cheddar</h4>
<p>This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content.</p>
<h4>Gouda</h4>
<p>Howda you say "gouda?" This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content.</p>

<p>This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content.</p>
<h4>Swiss</h4>
<p>This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.This is nonsense paragraph content. This is nonsense paragraph content.</p>
<h3>The History of Cheese</h3>
<p>This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.</p>

<blockquote>This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.  This is nonsense paragraph content.</blockquote>
<p>This is nonsense paragraph content. This is nonsense paragraph content.</p>
<h3>How to Make Cheese</h3>
<p>This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.  This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.</p>
<h4>"Farm Cheeses"</h4>
<p>This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content. This is nonsense paragraph content.</p>
<hr id="answer">
<h2>Answer</h2>
<details>
	<summary>Display heading error</summary>
	<p>There is a "gap" in the heading structure because there is no Heading 2.</p>
</details>
<details>
	<summary>Display heading fix</summary>
	<p>To make a logical page outline, each Heading 3 on this page (e.g. "Types of Cheese") should be a Heading 4. To follow, each Heading 4 (e.g. "Cheddar"), should be a Heading 3.</p>
</details>
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CSS 

              
                * {
	margin: 0;
	box-sizing: border-box;
}
* + * {
	margin-top: 1.5em;
}
html {
	background: #eee;
}
body {
	max-width: 740px;
	padding: 30px;
	margin: 0 auto;
	background: #fff;
	font-size: 1.25rem;
	line-height: 1.5;
	font-family: sans-serif;
	color: #222;
}
h1 small {
	display: block;
	font-size: 1.25rem;
	color: #777;
}

summary {
	color: blue;
	text-decoration: underline;
	cursor: pointer;
	&:hover,
	&:focus {
		text-decoration: none;
		color: darkblue;
	}
}

blockquote {
	border-left: 10px solid #ccc;
	padding-left: 30px;
	font-size: 1.375rem;
	color: #555;
}
li + li {
	margin-top: .3em;
}

.meta {
	font-style: italic;
	background: #eee;
	border: 1px solid #ddd;
	padding: 10px;
	font-size: 1rem;
}
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JS
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999px

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