Author: A M Robiul Islam | Published at: 19 Sep 2024

CSS pseudo-selectors are an essential part of modern web design. They allow developers to style elements dynamically based on their state, position, or other conditions that regular CSS selectors can’t handle. If you're working on building an interactive, dynamic, and visually appealing website, mastering CSS pseudo-selectors is crucial. In this article, we’ll break down what CSS pseudo-selectors are, explain how they work, and show you practical examples to implement them.

What Are CSS Pseudo Selectors?

CSS pseudo-selectors are used to define the special state of an element. They allow you to target elements that cannot be selected by a simple CSS selector. For instance, you can style an element when a user hovers over it, selects a form input, or clicks on a link. Pseudo-selectors are great for creating user interactivity, dynamic effects, and custom stylings without needing JavaScript.

Pseudo-selectors come in two main types:

• Pseudo-classes: These define a special state of an element, like :hover, :focus, or :nth-child().
• Pseudo-elements: These select parts of an element, like ::before, ::after, or ::first-letter.

Now, let’s dive into the most commonly used CSS pseudo-selectors.

Common CSS Pseudo-Classes

1.

The :hover pseudo-class applies a style to an element when a user hovers over it with the mouse. This is often used to make buttons or links more interactive.

a:hover {
  color: red;
  text-decoration: underline;
}

Example Use Case: If you want a button to change color when users hover over it, :hover is perfect for this. It improves user experience by providing feedback when interacting with elements.

2.

The :focus pseudo-class targets an element that is currently selected or focused by the user, often when using the keyboard or interacting with forms. This is critical for accessibility, allowing users to see which element is selected.

input:focus {
  outline: 2px solid blue;
  background-color: lightyellow;
}

Example Use Case: For form inputs, :focus can highlight the current input field, helping users identify where they are on the page.