How so? If you utilize Jekyll you merely move the text content from HTML to markdown. Essentially strongly separating content and presentation.
But this is the inverse of creating a site in Markdown and 'translating' it to HTML.
HTML to Markdown is trivial, infact IIRC Markdown will support HTML tags.
Creating a Good looking site like OP's in markdown would be ridiculous, if even possible at all.
How so? If you utilize Jekyll you merely move the text content from HTML to markdown. Essentially strongly separating content and presentation.