Improving Tufte CSS for Jekyll

2019-11-01

After creating the ET-Jekyll theme almost two years ago, I finally got around to revamping the structure and improving a lot of minor performance issues. Items that have been surely needing of updates for the last couple of years.

Introductions

I've always been a sucker for Edward Tufte's incredibly simple, yet powerful design work used in his books and handout projects. So, in 2018 I released a Tufte CSS inspired Jekyll theme for the open source community. I called it ET-Jekyll (so original, I know). Tufte CSS was a great starting point for my Jekyll theme, but there were areas I thought could use some minor improvements.

Feel free to read all the details on the design here: ET-Jekyll theme details

Minor Fixes One Year Later

When I finally circled back to this project recently, I noticed some minor issues that could be improved right away with little to no effort. Let's see the changes made at a glance:

• Sidenote, marginnote and figure element restyling (flexbox)
• Table styling fixes (right alignment issues)
• Switch MathJax over to SVG embeds (performance fixes)
• Simplify HTML skeleton of main pages, remove overkill classes
• Remove lazysizes.js to save on load times
• Fallback on font-display for font loading
• Inline all CSS for faster initial paint
• Minor link :hover coloring (accessibility)
• Add missing image link on example page
• Update details post structure

You can view all the updates in more detail here.

So what did this accomplish? Let's break it down below.

First Contentful Paint & Input Delay

The new improvements have netted the theme a savings of 300ms on first paint and reduced the input delay by 150ms. Small wins - but wins nonetheless since every millisecond counts.

Fixing Render Blocking Items

The original theme reported a few items that were slowing down the initial render for the end-users:

These items were resolved by:

• Rendering all styling inline (therefore removing the extra HTTP request)
• Removing the lazysizes library altogether (browsers plan to support lazy loading natively in the future)
  • The future plan is to integrate something like Cloudinary for out-of-the-box image processing
• Switch over MathJax to render equations as embedded SVGs (saves on bandwidth rendering an entire extra typeface)

Lighthouse Numbers

Though it might not look like much, the updated theme receives a 4-point boost to its performance rating during a Lighthouse audit. Having a perfect score would be even better, but I can settle for 2-points under (for now).

Old Version

New Version

Final Thoughts

This project could still use some more fine-tuning, but for now I'm fairly happy with the outcome. Even the smallest boost in performance and rendering time makes me feel like I accomplished something worthwhile.

Please don't hesitate to suggest features or point out any issues you happen to stumble across if you plan to use ET-Jekyll. Thanks for reading!