The marketing for Core Web Vitals (CWV) has been a massive success. I guess that’s what happens when the world’s dominant search engine tells people that something’s going to be an SEO factor. Ya know what language can play a huge role in those CWV scores? I’ll wait five minutes for you to think of it. Just kidding, it’s CSS.
Katie Hempenius and Una Kravets:
The way you write your styles and build layouts can have a major impact on Core Web Vitals. This is particularly true for Cumulative Layout Shift (CLS) and Largest Contentful Paint (LCP).
For example…
- Absolutely positioning things takes them out of flow and prevents layout shifting (but please don’t read that as we should absolute position everything).
- Don’t load images you don’t have to (e.g. use a CSS gradient instead), which lends a bit of credibility to this.
- Perfect font fallbacks definitely help layout shifting.
There are a bunch more practical ideas in the article and they’re all good ideas (because good performance is good for lots of reasons), even if the SEO angle isn’t compelling to you.