template.html

<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://sindresorhus.com/github-markdown-css/github-markdown.css">

<style>
	body {
		font-family: Helvetica;
		font-size: 20px;
		box-sizing: border-box;
		min-width: 200px;
		max-width: 980px;
		margin: 0 auto;
		padding: 45px;
	}

	.sidenav {
		font-size: 14px;
		float: left;
		height: 100%;
		width: 160px;
		list-style: none;
	}

	.sidenav ul {
		list-style: none;
	}

	article {
		float: right;
		max-width:600px
	}

	iframe {
		width: 100%;
		max-width: 640px;
	}

	.video-container {
		position:relative;
		padding-bottom:56.25%;
		padding-top:30px;
		height:0;
		overflow:hidden;
	}

	.video-container iframe, .video-container object, .video-container embed {
		position:absolute;
		top:0;
		left:0;
		width:100%;
		height:100%;
	}

	@media (max-width: 767px) {
		body {
			padding: 15px;
		}

		.sidenav {
			display: none;
		}
	}

	.header ul {
		list-style: none;
		padding-left: 0px;
	}
</style>

<div class="header">
	{{{navbar}}}
</div>

<div class="sidenav">
	{{{sidebar}}}
</div>

<article class="markdown-body" style="font-size: 20px;">
	{{{main_content}}}
</article>