My old personal web site served me well since 1998, but in this mobile world, that old frames-based site needed to be responsive to modern devices.
I found a site template at html5up that had most of the features I liked, but it was static HTML5. Wanting to prepare my site for a blog and portfolio, I chose to apply Jekyll to the template for easier post authoring.
I released a Jekyll version of the simple template on github, a version that can be used for sites with just a few pages. I also forked a version to be applied to a more full-featured blog site with many pages like mine. During the process, not only did I learn Jekyll and some Ruby, but I also learned some SASS and a bit about how to apply styles that are screen-responsive.