<p>CSS selectors are patterns used to select elements in HTML documents. They include element selectors, class selectors, ID selectors, wildcard selectors, and descendant selectors. The syntax of a selector is selector name, operator, and value. Operators include # (ID selector), . (class selector), and * (wildcard selector). When multiple selectors are applied to the same element, the most specific (longest) selector will take precedence. Advanced selectors include adjacent selectors, child element selectors, pseudo-class selectors, and pseudo-element selectors for more precise element selection.
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CSS Selector Writing Guide
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What is a CSS selector?
<p>CSS selectors are patterns used to select specific elements in an HTML document.
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Selector type
-
Element selector: Select a specific type of element, such as
<div>
or <p>
.
-
Class selector: Selects elements with a specific CSS class name, such as
.my-class
.
-
ID selector: Select elements with a specific ID attribute, such as
#my-id
.
-
Wildcard selector:Select all elements, such as
*
.
-
Descendant selector: Select descendant elements of an ancestor element, such as
div p
.
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Selector syntax
<p>A selector consists of three main parts:
-
Selector name: Specify element type or attribute
-
Operator: Usually used to specify specific conditions
-
Value: Specific value of the selector
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Operators for selectors
-
:
- Specify the class selector
-
# - Specify the ID selector
-
.
: Specify the wildcard selector
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The cascade of selectors
<p> When multiple selectors are applied to the same element, the most specific (longest) selector will take precedence.
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Example
-
#my-id
- Select elements with ID attribute "my-id"
-
.my-class
- Selects elements with CSS class name "my-class"
-
div p
- Selects all <div>
Descendants of elements<p>
Elements
-
*
- Select all elements
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Advanced Selector
<p>In addition to the basic selector types, CSS also supports advanced selectors:
-
Adjacent selector ( ): Selects an element immediately following another After the element, such as
p h1
- ##Child element selector (>): Select the direct child element of an element, such as div > p
- Pseudo-class selector: Select based on the state or behavior of the element, such as :hover
- Pseudo-element selection Selector: Select a specific part of an element, such as ::after
By understanding these selectors and their use, you can effectively select elements in your HTML document to Make style settings. <p>
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