<commit_before>---
title: Native CSS Feature Detection via the @supports Rule
authors:
- chris-mills
layout: article
---<commit_msg>Add intro for article “Native CSS Feature Detection via the `@supports` Rule”<commit_after>---
title: Native CSS Feature Detection via the `@supports` Rule
authors:
- chris-mills
intro: 'We have practised feature detection to allow us to provide appropriate code to browsers with differing levels of standards support for a while now, but we’ve always needed 3rd party libraries to handle it. But not for much longer: the CSS3 Conditional Rules Module Level 3 provides the `@supports` at-rule and associated JavaScript API, providing a native mechanism for doing CSS feature detection. In this article we’ll give you the lowdown on how this rule works, looking at a real example in the process.'
layout: article
---
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