CSS Advent Calendar

The Advent season is just around the corner, and I'm excited to present our CSS Advent Calendar! 🎄

Starting December 1st, 2025, you can expect a new, independent article about Cascading Style Sheets (CSS) every day until Christmas. Whether it's exciting tips, useful tricks, or just interesting information – there's something for everyone, regardless of whether you're a junior or senior developer.

Let's fill the days until Christmas together with new knowledge and fun.

Featured

• Day 25 – Browser Support. What can we use today?

  Published:Dec 25, 2025 |  at 07:00 AM

  A comprehensive overview of browser support for all CSS features covered in this advent calendar. From stable standards to experimental APIs. Find out what you can use in production today.

Recent Posts

• Door 24 – CSS for Design Systems

  Published:Dec 24, 2025 |  at 07:00 AM

  CSS for design systems is more than styling. It is architecture, governance, and consistent engineering. This door shows how to use CSS strategically and that with tokens, layers, component-oriented structures, and scalable patterns.

• Door 23 – CSS Debugging

  Published:Dec 23, 2025 |  at 07:00 AM

  Debugging CSS is often more difficult than writing it. This door shows proven debugging strategies, mental models, and tools that can save a lot of time in large codebases.

• Door 22 – CSS Houdini

  Published:Dec 22, 2025 |  at 07:00 AM

  CSS Houdini opens CSS to developers. Paint API, Properties & Values API, Typed OM, and more. This door explains what is possible, where it is already in use, and why Houdini is shaping the future of the CSS engine.