CSS @supports: Write Future-Proof CSS

Detect CSS feature support and provide smart fallbacks with @supports

Trevor I. Lasn Trevor I. Lasn
· 3 min read
Building 0xinsider.com, the intelligence layer for prediction markets. Discover what's moving, see who's behind it, and find the edge before the crowd.

I use @supports constantly to check if browsers can handle modern CSS features. Think of it as a safety net for your styles - if a browser doesn’t support a feature, you can provide a solid fallback.

Here’s what it looks like in practice:


How @supports Works

The @supports rule checks if a browser understands a CSS property-value pair. You can test for single or multiple features:

Here’s how I use @supports to progressively improve a layout:


Testing Multiple Properties

Sometimes you need to test for multiple CSS properties. Here’s how to handle complex feature detection:


Best Practices

  1. Start with solid fallback styles that work everywhere
  2. Use @supports to enhance the experience with modern features
  3. Test features individually when possible
  4. Consider using multiple @supports rules for different feature combinations
  5. Keep fallback code maintainable - don’t create overly complex style overrides

Trevor I. Lasn

Building 0xinsider.com, the intelligence layer for prediction markets. Discover what's moving, see who's behind it, and find the edge before the crowd. Product engineer based in Tartu, Estonia, building and shipping for over a decade.


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This article was originally published on https://www.trevorlasn.com/blog/detect-css-features-with-supports-property. It was written by a human and polished using grammar tools for clarity.