What is a pseudo-class pseudo-element?

Pseudo-classes and pseudo-elements are special selectors in CSS that are used to select a specific state or part of an element and apply styles to it. Pseudo-classes are selectors used to select a specific state or behavior of an element. They start with a colon (:) and are used to select elements in a specific state. Pseudo-elements are selectors used to select a specific part of an element or generate content. They start with a double colon (::) and are used to select a specific part of an element or to generate content before or after an element. Developers need to follow certain syntax rules and conduct compatibility testing when using pseudo-classes and pseudo-elements.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

In CSS, pseudo-classes and pseudo-elements are special selectors used to select specific elements or specific states of elements in an HTML document. They allow developers to apply styles based on an element's content, structure, state, or position.

Pseudo-classes are selectors used to select a specific state or behavior of an element. They start with a colon (:) and are used to select elements in a specific state, for example:hover is used to select the state of the mouse hovering over the element, :active is used to select the state of the clicked element, :focus is used to select the obtained The state of the focused form element, etc. Pseudo-classes can be used in conjunction with normal selectors to select elements more precisely.

Pseudo elements are selectors used to select specific parts of an element or generate content. They start with a double colon (::) and are used to select a specific part of an element or to generate content before or after an element. Common pseudo-elements include ::before for generating content before an element, ::after for generating content after an element, ::first-letter for selecting the first letter of an element, and ::first-line for selecting first row of elements etc. Pseudo-elements can be used in conjunction with normal selectors to more precisely select specific parts of an element.

The use of pseudo-classes and pseudo-elements can provide developers with more style control and layout options. They can be used to create special effects, enhance user experience, adjust layouts, and more. For example, you can use pseudo-classes and pseudo-elements to create mouseover effects, add icons or decorations, adjust text styles, and more.

It should be noted that the use of pseudo-classes and pseudo-elements must follow certain grammatical rules. Different pseudo-classes and pseudo-elements have different syntax and usage, and developers need to choose and use them according to specific situations. In addition, different browsers have different levels of support for pseudo-classes and pseudo-elements, and developers need to conduct compatibility testing when using them.

To summarize, pseudo-classes and pseudo-elements are special selectors in CSS that are used to select a specific state or part of an element and apply styles to it. They provide more style control and layout options that can be used to create special effects, enhance user experience, adjust layout, and more. Developers need to follow certain syntax rules and conduct compatibility testing when using pseudo-classes and pseudo-elements.

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