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HTML

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CSS

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JavaScript

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HTML 

              
                	<nav>
		<ul class="nav">
			<li><a href="">Chapter 1</a></li>
			<li><a href="">Chapter 2</a></li>
			<li><a href="">Chapter 3</a></li>
<li><a href="">Chapter 5</a></li>
			<li><a href="">Chapter 6</a></li>
		</ul>
	</nav>

	<article class="main content">
	   <h1>Chapter 1</h1>

  <p>When the first strong sunlight of May covered the tree-arched avenues
  of Center City with green, the riots started.</p>
  
  <p>The people gathered in angry knots outside the city hall, met in the park and littered its walks with newspapers and magazines as they gobbled up editorial comment at a furious rate, slipped with dark of night through back alleys and planned things with furious futility.</p>
  
  <p>Center City's finest knew when to make themselves scarce: their uniforms stood for everything objectionable at this time and they might be subjected to clubs, stones, taunts, threats, leers--and knives.</p>
  
  <p>But Center City, like most communities in United North America, had survived the Riots before and would survive them again. On past performances, the damage could be estimated, too. Two-hundred fifty-seven plate glass windows would be broken, three-hundred twelve limbs fractured. Several thousand people would be treated for minor bruises and abrasions, Center City would receive half that many damage suits. The list had been drawn clearly and accurately; it hardly ever deviated.</p>
    
  <p>And Center City would meet its quota. With a demonstration of reluctance, of course. The healthy approved way to get over social trauma once every seven-hundred eighty days.</p>
	</article>

	<footer class="footnotes content">
		<p>Text from the public domain book Recruit for Andromeda by Milton Lesser available on <a href="http://www.gutenberg.org/cache/epub/50449/">the Project Gutenberg website</a>.</p>

	</footer>
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CSS 

              
                body {
	margin: 0;
	padding: 40px;
}

.content {
	background-color: #fdfdfd;
	padding: 20px;
	margin: 0 0 1em 0;
}

ul.nav {
	list-style: none;
	margin: 0;
	padding: 0;
	margin: 0 0 1em 0;
}

ul.nav li {
	border: 1px solid #444;
	background-color: #fff;
}

ul.nav li a {
  padding: 20px 40px;
  text-decoration: none;
  display: block;
  color: #444;
	font-weight: bold;
}

nav ul{
  display: flex;
  flex-direction: row;
  justify-content: space-between;
}

@media (max-width: 800px) {
  nav ul {
    flex-wrap: wrap;
  }
  
  nav ul li {
    flex: auto;
    margin: 0 10px 10px 0;
  }
}
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JS
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999px

Console