How to write css selector

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.

CSS Selector Writing Guide

What is a CSS selector?

CSS selectors are patterns used to select specific elements in an HTML document.

Selector type

• Element selector:Select a specific type of element, such as
  or

  .

• 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 asdiv p.

Selector syntax

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

Operators for selectors

• :- Specify the class selector
• # - Specify the ID selector
• .: Specify the wildcard selector

The cascade of selectors

When multiple selectors are applied to the same element, the most specific (longest) selector will take precedence.

Example

• #my-id- Select elements with ID attribute "my-id"
• .my-class- Selects elements with CSS class name "my-class"
• div p- Selects all
  Descendants of elements

  Elements

• *- Select all elements

Advanced Selector

In addition to the basic selector types, CSS also supports advanced selectors:

• Adjacent selector ( ):Selects an element immediately following another After the element, such asp h1
• ##Child element selector (>):Select the direct child element of an element, such asdiv > 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

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