CSS Custom Properties
CSS Custom Properties, also known as CSS Variables, are a feature in CSS that allows developers to define reusable values in a stylesheet, which can be referenced and manipulated dynamically using JavaScript. They enable the creation of themes, responsive designs, and maintainable code by centralizing style values. Unlike preprocessor variables, they are native to the browser and can be updated at runtime.
Developers should learn CSS Custom Properties to build scalable and themeable web applications, as they simplify style management and enable dynamic theming without recompiling CSS. They are particularly useful for design systems, dark mode implementations, and responsive adjustments where values need to change based on user interactions or viewport sizes. This reduces code duplication and enhances maintainability in large projects.