CSS properties - CSS | MDN

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A CSS property is a parameter used in a CSS declaration that lets you style certain aspects of selected elements. For example, the opacity property is used to set the opacity of a selected element, allowing you to control if content behind that element is visible:
Each property has a name (e.g., opacity), a value (e.g., 0.8), and a defined behavior on the rendering of the document. CSS also defines shorthand properties, so you can specify multiple related properties in a single declaration. For example, the margin property is a shorthand for margin-top, margin-right, margin-bottom, and margin-left, setting the margin of all four sides of an element:
Standard properties defined by CSS specifications include the following:
Non-standard vendor-prefixed properties include:
This page was last modified on Jul 24, 2026 by MDN contributors.
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