How to use css selector

<p>CSS selectors are used to select elements from HTML documents. Types include: Element Selector: Selects a specific element type. Class selector: Selects elements whose class name matches. ID selector: Selects elements whose ID matches. Wildcard selector: selects all elements. Descendant selector: Selects descendants of ancestor elements. Derived selector: selects elements whose attributes or values ​​match.

<p>

<p>Introduction to CSS Selectors

<p>CSS selectors are syntax rules used to select elements from an HTML document. By using selectors, we can apply styles, add behaviors, or manipulate specific HTML elements in JavaScript.

<p>Selector type

<p>CSS provides a variety of selector types, including:

• Element selector: Select a specific type of element, such as <p> or <div>.
• Class selector: Select elements with a specific class name, such as .my-class.
• ID selector: Selects elements with a specific ID, such as #my-id.
• Wildcard selector: Select all elements, such as *.
• Descendant selector: Selects descendant elements of the specified element, such as p a.
• Derived selector: Select elements with specific attributes or values, such as [type=submit].

<p>Selector syntax

<p>The selector syntax consists of the selector type and optional qualifiers. Qualifiers can narrow the scope of a selector.

<p>For example:

• .my-class Selects all elements with the class name "my-class".
• p:hover Selects all elements that have a <p> element on mouse hover.

<p>Using selectors

<p>To use a selector, add it to a selector block in your CSS stylesheet. The selector block specifies the style of the selected element.

<p>For example:

<code class="css">.my-class {
  color: blue;
}</code>

<p>This will set the text color to blue for all elements with the class name "my-class".

<p>Complex Selectors

<p>You can also combine multiple selectors to create more complex selectors. For example:

• div.container p Selects all <p> in a <div> element with class name "container" elements.
• #my-id a:hover Selects all <a> elements within the element with ID "my-id" on mouseover.

<p>Selector priority

<p>When multiple selectors are applied to the same element, the selector with higher priority will be applied. Priority is determined by the selector type, qualifiers, and the order of the elements.

<p>Conclusion

<p>CSS selectors are basic tools for selecting elements from HTML documents. By understanding the different types of selectors and their syntax, we can effectively apply styles and manipulate page elements.

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