as of 2013.01.28
Based on Kevin Burke's markdowncss idea, I created this alternative CSS. The main purpose is, to style my own .md files.
You can use this by insert
<link href="https://raw.github.com/senki/Markdown/master/markdown.css" rel="stylesheet"></link>
to top of your Markdown file.
Updated on 2014.05.08.
Rescale Font sizes based on A More Modern Scale for Web Typography.