What are the global selectors?

Global selectors include wildcard selector, :root selector, :empty selector, :not selector, :target selector and :checked selector, etc. Detailed introduction: 1. Wildcard selector, using "*" as the selector, means selecting all elements. This is the simplest global selector and can be used to select all elements in the page; 2. :root selector is used to select The root element of the document is usually the "" element. You can define styles for the root element through the :root selector; 3. :empty and so on.

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

Global selectors are a special type of selector in CSS that are used to select all elements in the document regardless of the element's type, position, or other attributes. Global selectors help developers apply styles to the entire page. The following are some common global selectors:

1. *: Universal Selector: Use `*` as a selector to select all elements. This is the simplest global selector and can be used to select all elements on the page.

2. :root::root selector is used to select the root element of the document, usually the `` element. You can define styles for the root element through the :root selector.

3. :empty: The :empty selector is used to select elements that have no child elements. You can define styles for elements with no content through the :empty selector.

4. :not(selector): The :not selector is used to select elements that do not match the specified selector. You can exclude certain elements and only select other elements through the :not selector.

5. :target::target selector is used to select the currently active target element, that is, the anchor target specified in the URL. You can define styles for the currently active target element through the :target selector.

6. :checked: The :checked selector is used to select the selected check box or radio button. You can use the :checked selector to define styles for selected check boxes or radio buttons.

These global selectors can be combined with other selectors for more precise style selection and application. Global selectors play an important role in CSS and help developers apply styles to the entire page.

It should be noted that the global selector has a high weight and may have an impact on the performance of the entire page. Therefore, when using global selectors, you should use them with caution and make sure you only use them when necessary.

In summary, common global selectors include wildcard selectors, :root selectors, :empty selectors, :not selectors, :target selectors and :checked selectors. By using these global selectors, developers can apply styles to the entire page. I hope the above answer is helpful to you, if you have any other questions, please feel free to let me know.

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