Kilian Valkhof

Building tools that make developers awesome.

:root isn’t global

CSS & HTML, 1 May 2023

Most developers prefer to keep all their CSS custom properties in one place, and a pattern that has emerged in recent years is to put those on :root, a pseudo-class that targets the topmost element in your document (so that's always <html> on web pages). But just because they're in one place and in the topmost element, it doesn't mean they're global.

A small JavaScript pattern I enjoy using

Javascript, 3 April 2023

There is a JavaScript pattern that I enjoy using that I don’t see a lot around the web, so I figured it would be worth sharing.

I no longer understand prefers-contrast

CSS & HTML, 8 March 2023

The prefers-contrast media query indicates whether someone prefers more or less contrast within the boundaries of your sites design. At least, that’s what I thought it meant, and it’s also how macOS seems to implement it with their ‘increase contrast’ accessibility feature. This is in contrast to the forced-colors media query, which overwrites all your styles.

::backdrop doesn’t inherit from anywhere

CSS & HTML, 19 January 2023

Earlier this month I was implementing a lightbox for using <dialog>. I'll be writing about that soon but you can find the implementation in that link, it's remarkable how little code you need. While styling, I made use of the CSS custom properties that where already defined in the CSS to style the dialog and it's backdrop. Or so I thought.

I was on the podcast to talk about Polypane

Web, 4 January 2023

Last Friday I went on the Supper Club podcast to chat with Scott and Wes about everything Polypane. We go pretty deep into some of the features and in hindsight it’s funny how most of it boils down to “I needed this feature so I built it”. I had a great time geeking out about it so thank you Scott and Wes for having me!

Polypane browser for responsive web development and design Hi, I'm Kilian. I make Polypane, the browser for responsive web development and design. If you're reading this site, that's probably interesting to you. Try it out!

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Demo your (bot) interactions on Messenger.