This was forked to remove HTML5 dependencies for older browsers such as those built into old versions of Eclipse.
The minimal amount of CSS to replicate the GitHub Markdown style
Download manually
Import the github-markdown.css file.
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="github-markdown.css">
<body>
<h1>Unicorns</h1>
<p>All the things</p>
</body>MIT © Sindre Sorhus