CSS :visited Selector

The :visited selector in CSS is an important concept for web developers aiming to enhance user experience through styling links based on their visited state. This article serves as a comprehensive guide for beginners to understand what the :visited selector is, its applications, limitations, and best practices.

I. Introduction

A. Definition of the :visited selector

The :visited selector is a pseudo-class in CSS that allows web developers to apply specific styles to hyperlinks that the user has previously visited. It helps signal to a user which links they have already explored on a website.

B. Purpose of the :visited selector in CSS

The primary purpose of the :visited selector is to enhance user navigation and experience. By visually distinguishing between visited and unvisited links, users can efficiently manage and traverse the available links, making the web browsing experience more intuitive.

II. Browser Support

The :visited selector is widely supported across all modern browsers, including:

Browser	Version	Support
Chrome	All versions	✅
Firefox	All versions	✅
Safari	All versions	✅
Edge	All versions	✅
Internet Explorer	9+	✅

III. How to Use the :visited Selector

A. Syntax of the :visited selector

The syntax for the :visited selector is straightforward:

selector:visited {
        /* CSS Properties */
    }

B. Examples of applying the :visited selector

Below are examples demonstrating how to use the :visited selector:

Example 1: Changing Color of Visited Links

/* Link styles */
a {
    color: blue;
    text-decoration: none;
}

/* Visited link styles */
a:visited {
    color: purple;
}

In this example, all hyperlinks are styled with blue color, and once the link is visited, it changes to purple.

Example 2: Underlining Visited Links

/* Link styles */
a {
    color: green;
    text-decoration: none;
}

/* Visited link styles */
a:visited {
    color: red;
    text-decoration: underline;
}

In this second example, unvisited links appear in green, while visited links turn red and are underlined.

Responsive Example

This snippet shows a responsive approach that changes link color based on viewport width:

@media (max-width: 600px) {
    a {
        color: orange;
    }
    
    a:visited {
        color: darkorange;
    }
}

@media (min-width: 601px) {
    a {
        color: blue;
    }
    
    a:visited {
        color: purple;
    }
}

IV. Limitations of the :visited Selector

A. Restrictions on styles that can be changed

While the :visited selector is powerful, it has significant limitations. For privacy and security reasons, browsers restrict the properties that can be modified using :visited. The properties that can be used include:

• color
• background-color
• border-color
• outline-color

Other properties, such as font-size or visibility, cannot be changed for visited links.

B. Impact on privacy and security

Changing styles for visited links could inadvertently expose a user’s browsing history. If malicious websites could detect the styles of visited links, they’ll be able to infer which sites a user has visited. As a result, browsers implement these restrictions to protect user privacy.

V. Conclusion

A. Summary of key points

The :visited selector allows developers to style links based on whether or not a user has visited them. It enhances user navigation, but it comes with limitations and privacy considerations.

B. Importance of understanding the :visited selector in web design

Understanding the :visited selector is essential for creating intuitive and user-friendly web applications. As a developer, being knowledgeable about link states will empower you to craft more effective designs that cater to user needs.

FAQ

1. Can I style visited links with any CSS property?

No, due to privacy concerns, only specific properties such as color, background-color, and border-color can be modified.

2. Will the :visited selector work with all types of links?

Yes, the :visited selector works with all HTML anchor links, regardless of their destination.

3. How do browsers handle the :visited selector for privacy?

Browsers limit the CSS properties that can be changed for visited links to prevent websites from tracking users based on their link styles, thereby ensuring user privacy.

4. Can I use scripts or libraries to bypass the limitations of the :visited selector?

No, bypassing these limitations would also compromise user privacy, and reputable browsers will not allow it as part of their security measures.

5. Is the :visited selector part of CSS3?

The :visited selector is part of CSS2 and has been carried forward into CSS3 with the same limitations and functionalities.