Providing Type Definitions for CSS with @property

A cross-browser feature as of the release of Firefox 128 in July 2024 is a new at-rule – @property – which allows defining types as well as inheritance and an initial value for your custom properties.

We’ll learn when and why traditional fallback values can fail, and how @property features allow us to write safer, more resilient CSS custom property definitions.

Source: Providing Type Definitions for CSS with @property | Modern CSS Solutions