What is a front-end pseudo-element? What is a front-end pseudo-element?-Front-end Q&A-php.cn

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What are front-end pseudo-elements?

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Oct 09, 2023 pm 05:22 PM

front endPseudo element

Front-end pseudo-element is a special selector in CSS that allows developers to insert additional content before or after HTML elements. Pseudo-elements are represented by using double colons, which are the same as single pseudo-classes. Unlike colons, pseudo-elements can be used to insert decorative content before or after the content of an element without adding additional markup in the HTML. Its use is indicated by using a double colon after the selector in the CSS style sheet. , common pseudo-elements include before, after, first-line and first-letter.

What are front-end pseudo-elements?

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

Front-end pseudo-element is a special selector in CSS that allows developers to insert additional content before or after HTML elements. Pseudo-elements are represented by using a double colon (::), as opposed to the single colon (:) of pseudo-classes. Pseudo-elements can be used to insert decorative content before or after the content of an element without adding additional markup in HTML.

Pseudo elements are used by using a double colon (::) after the selector in the CSS style sheet. Common pseudo-elements include: before, after, first-line and first-letter.

1. before pseudo-element: The before pseudo-element is used to insert content before the content of the selected element. Inserted content can be defined using the content property and styled using other CSS properties. For example, you can use the before pseudo-element to insert an icon or decorative content before a paragraph.

2. after pseudo-element: The after pseudo-element is similar to the before pseudo-element, but it inserts content after the content of the selected element. Inserted content can also be defined and set using the content property and other CSS properties.

3. first-line pseudo-element: The first-line pseudo-element is used to select the first line of text of the selected element. You can use this pseudo-element to style the first line of text, such as changing fonts, colors, etc.

4. first-letter pseudo-element: The first-letter pseudo-element is used to select the first letter of the selected element. You can use this pseudo-element to style the first letter, such as changing the font size, color, etc.

Using pseudo elements can add some decorative effects to web pages without adding additional tags to HTML. They provide a simple and flexible way to change the appearance of elements, giving developers greater control over the style of web pages.

It should be noted that pseudo elements can only be used for block-level elements and not for inline elements. In addition, the content generated by pseudo elements is not a real DOM element and cannot be accessed or manipulated through JavaScript.

In summary, the front-end pseudo-element is a special selector in CSS that is used to insert additional content before or after HTML elements. By using pseudo-elements such as before, after, first-line, and first-letter, developers can add decorative effects to web pages while maintaining the simplicity and semantics of HTML structure.

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