What are the css3 selectors?

CSS3 selectors are part of CSS3 and are used to select elements in HTML documents. They can select elements based on criteria such as their type, attributes, status, and location.

The following are some commonly used CSS3 selectors and their code examples:

1. Element Selector (Element Selector):
   Select elements by their names.

   Sample code:

   p {
     color: red;
   }

   The above code will select all <p></p> elements and set their color to red.

2. Class Selector:
   Select elements through their class attribute.

   Sample code:

   .highlight {
     background-color: yellow;
   }

   The above code will select all elements with the "highlight" class and set their background color to yellow.

3. ID Selector:
   Select elements through their id attribute.

   Sample code:

   #main-title {
     font-size: 24px;
   }

   The above code will select the element with the "main-title" id and set its font size to 24 pixels.

4. Attribute Selector:
   Select elements by their attribute values.

   Sample code:

   input[type="text"] {
     border: 1px solid gray;
   }

   The above code will select all input elements whose type attribute is "text" and set their borders to gray.

5. Pseudo-class Selector:
   Select elements through their special status, such as :hover, :nth -child() etc.

   Sample code:

   a:hover {
     color: blue;
   }

   The above code will select the <a></a> element when the mouse is hovering over the link, and set its color to blue.

6. Pseudo-element Selector:
   Select elements through their special positions, such as ::before, : :after etc.

   Sample code:

   p::before {
     content: "Chapter: ";
     font-weight: bold;
   }

   The above code will add a pseudo element with the content "Chapter: " in front of each <p></p> element and add it The font is bold.

This is just a small selection of CSS3 selectors, there are many other selectors available for more specific selection. By using these selectors appropriately, you can more precisely select and style elements in your HTML document.

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