How Does Cascading Determine Style Application in CSS?

Understanding the Meaning of Cascading in CSS: A Comprehensive Guide

CSS stands for Cascading Style Sheets, and as the name suggests, the term "cascading" plays a crucial role in understanding how styles are applied to HTML elements. In essence, cascading refers to the mechanism by which multiple stylesheet declarations can be applied to the same HTML element, and there's a defined order of precedence to determine which specific rule takes effect.

How Cascading Works in CSS

Let's consider a simplified example to illustrate how cascading operates:

In this example, the body rule is defined in a global stylesheet that applies to the entire document. The #my-paragraph rule is declared in a more specific stylesheet that only targets the

element with the id of "my-paragraph."

According to the principle of cascading, the more specific rule takes precedence over the general rule. Therefore, the #my-paragraph rule will be applied to the

element, overriding the body rule's font size and color properties.

Cascading Order

The order of precedence in CSS cascading is determined by three factors:

• Specificity: The more specific a selector is, the higher its precedence.
• Origin: Styles defined in the user-agent (browser) have the lowest precedence, followed by those defined in the author stylesheet, and then by those defined in the user stylesheet.
• Order of appearance: If two rules have the same specificity and origin, the latter one declared in the stylesheet takes precedence.

By understanding these principles, developers can effectively tailor the visual presentation of HTML elements based on the cascading rules. The official W3C specification on cascading provides further detailed information: https://www.w3.org/TR/css-cascade-4/.

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