danluu.com has the following style tag right at the start of the document: <style>d{width:4em}li{display:flex;margin:0 0 .9em}ul{margin:0;padding:0}.np{displ

danluu.com has the following style tag right at the start of the document: <style>d{width:4em}li{display:flex;margin:0 0 .9em}ul{margin:0;padding:0}.np{display:flex;flex-direction:row;justify-content:space-between;padding-bottom:.5em;font-style:italic}</style> He's not saying that you literally shouldn't have CSS. The important bit is "the site doesn't override any kind of default styling, letting you make the width exactly what you want (by setting your window size how you want it) and it also doesn't override any kind of default styling you apply to sites". It's the default styling that matters to him. Whenever someone complains that Dan Luu's site is unreadable and should have a font size of exactly 18px, that means their browser is configured to display text with a font size that is unreadable to them, which is easily remedied by changing their browser's default to 18px. And the best thing is that everyone can choose their own preferred value.