Imagine you are designing a navigation menu and you want the menu link to change color when a user hovers over it. Or perhaps you want to style the first paragraph of each section differently to highlight it. Pseudo-classes make all this possible, allowing you to select HTML elements based on their state or relation to other elements.

What are Pseudo-Classes?

A pseudo-class is a keyword added to selectors that specifies a special state of the selected element. For example, :hover can be applied to a link that the user is pointing to with the cursor.

Example of :hover

Let's make the links turn green when the user hovers over them.

Common Pseudo-Classes and Their Compatibility

In addition to :hover, there are many other pseudo-classes that you can use to design your web page more interactively and accessibly. Here are some of the most common ones that are compatible with most modern browsers:

• :first-child: selects the first child of an element.
• :last-child: selects the last child of an element.
• :nth-child(n): selects the nth child of an element.
• :nth-last-child(n): selects the nth child starting from the end.
• :not(selector): selects all elements that do not match the selector.
• :checked: selects form elements that are checked or selected.
• :focus: selects the element that has focus.
• :disabled: selects form elements that are disabled.
• :enabled: selects form elements that are enabled.

Example of :first-child

To give a special style to the first element of any container, we can use the :first-child pseudo-class.

Example of :last-child

Similarly, if you want to style the last element, you can use :last-child.

Conclusion

Pseudo-classes allow us to apply styles to elements based on their state, giving us great power to create dynamic and responsive user interfaces. By exploring and using these tools, you can significantly enhance your websites' user experience.

In the next topic, we will address pseudo-element selectors, which allow us to style specific parts of elements to create even more refined designs.