Pure CSS Off-screen Navigation Menuの使い方

下記ページを参考に各ファイル1式を作成。
Pure CSS Off-screen Navigation Menu
作成したファイルを任意の場所にコピー。

動作させるファイル（サンプルではindex.html）にコードを記述。
＜パスは上記ファイル構成の場合なので環境にあわせて変更＞
・head部分にcssファイルを読み込ませるためのコードを記述。

<head>
<!--作成したファイル-->
<link rel="stylesheet" type="text/css" href="css/style.css" />
</head>

サンプルのcssコード

* {
	margin: 0;
	padding: 0;
}
html, body {
	background: #fff;
	height: 100%;
}
body {
	overflow: hidden;
}
.navigation {
	/* critical sizing and position styles */
	width: 100%;
	height: 100%;
	position: fixed;
	top: 0;
	right: 0;
	bottom: 0;
	left: 0;
	z-index: 0;
	/* non-critical appearance styles */
	list-style: none;
	background: #111;
}
/* Navigation Menu - List items */
.nav-item {
	/* non-critical appearance styles */
	width: 200px;
	border-top: 1px solid #111;
	border-bottom: 1px solid #000;
}
.nav-item a {
	/* non-critical appearance styles */
	display: block;
	padding: 1em;
	background: linear-gradient(135deg, rgba(0,0,0,0) 0%, rgba(0,0,0,0.65) 100%);
	color: white;
	font-size: 1.2em;
	text-decoration: none;
	transition: color 0.2s, background 0.5s;
}
.nav-item a:hover {
	color: #c74438;
	background: linear-gradient(135deg, rgba(0,0,0,0) 0%, rgba(75,20,20,0.65) 100%);
}
/* Site Wrapper - Everything that isn't navigation */
.site-wrap {
	/* Critical position and size styles */
	min-height: 100%;
	min-width: 100%;
	background-color: white; /* Needs a background or else the nav will show through */
	position: relative;
	top: 0;
	bottom: 100%;
	left: 0;
	z-index: 1;
}
/* Nav Trigger */
.nav-trigger {
	/* critical styles - hide the checkbox input */
	position: absolute;
	clip: rect(0, 0, 0, 0);
}
label[for="nav-trigger"] {
	/* critical positioning styles */
	position: fixed;
	left: 15px;
	top: 15px;
	z-index: 2;
	/* non-critical apperance styles */
	height: 30px;
	width: 30px;
	cursor: pointer;
	background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' version='1.1' x='0px' y='0px' width='30px' height='30px' viewBox='0 0 30 30' enable-background='new 0 0 30 30' xml:space='preserve'><rect width='30' height='6'/><rect y='24' width='30' height='6'/><rect y='12' width='30' height='6'/></svg>");
	background-size: contain;
}
/* Make the Magic Happen */
.nav-trigger + label, .site-wrap {
	transition: left 0.2s;
}
.nav-trigger:checked + label {
	left: 215px;
}
.nav-trigger:checked ~ .site-wrap {
	left: 200px;
	box-shadow: 0 0 5px 5px rgba(0,0,0,0.5);
}

・<body></body>内にコードを記述

<ul class="navigation">
  <li class="nav-item"><a href="#">Home</a></li>
  <li class="nav-item"><a href="#">Portfolio</a></li>
  <li class="nav-item"><a href="#">About</a></li>
  <li class="nav-item"><a href="#">Blog</a></li>
  <li class="nav-item"><a href="#">Contact</a></li>
</ul>
<input type="checkbox" id="nav-trigger" class="nav-trigger" />
<label for="nav-trigger"></label>
<div class="site-wrap">
  <!-- insert the rest of your page markup here -->
</div>

サンプルのhtmlコード

<!DOCTYPE html>
<html lang="ja">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta charset="utf-8" />
<title>Pure CSS Off-screen Navigation Menu</title>
<link rel="stylesheet" type="text/css" href="css/style.css" />
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js" type="text/javascript"></script>
<![endif]-->
</head>

<body>
<ul class="navigation">
  <li class="nav-item"><a href="#">Home</a></li>
  <li class="nav-item"><a href="#">Portfolio</a></li>
  <li class="nav-item"><a href="#">About</a></li>
  <li class="nav-item"><a href="#">Blog</a></li>
  <li class="nav-item"><a href="#">Contact</a></li>
</ul>
<input type="checkbox" id="nav-trigger" class="nav-trigger" />
<label for="nav-trigger"></label>
<div class="site-wrap">
  <!-- insert the rest of your page markup here -->
</div>

</body>
</html>

ファイル1式をサーバーにアップロードして設置完了。