{"id":2065,"date":"2024-08-15T10:00:48","date_gmt":"2024-08-15T10:00:48","guid":{"rendered":"http:\/\/suimy.me\/?p=2065"},"modified":"2024-08-21T17:08:42","modified_gmt":"2024-08-21T17:08:42","slug":"comprehensive-guide-to-css-pseudo-classes-and-their-usage","status":"publish","type":"post","link":"http:\/\/suimy.me\/index.php\/2024\/08\/15\/comprehensive-guide-to-css-pseudo-classes-and-their-usage\/","title":{"rendered":"Comprehensive Guide to CSS Pseudo-Classes and Their Usage"},"content":{"rendered":"
Whether you\u2019re new to CSS or have years of experience, you\u2019ve likely encountered pseudo-classes<\/strong>. The most commonly recognized pseudo-class is probably Building on concepts from our previous discussions on margin:auto<\/a> and CSS Floats<\/a>, this post provides a detailed examination of pseudo-classes. We\u2019ll explore what pseudo-classes are<\/strong>, how they function, how they can be categorized, and how they differ from pseudo-elements<\/strong>.<\/p>\n A pseudo-class<\/a> is a keyword added to CSS selectors to define a specific state<\/strong> of an HTML element. You can add a pseudo-class to a CSS selector using the colon syntax<\/strong> A CSS class<\/a> is an attribute applied to HTML elements to enforce the same style rules, such as for top menu items or sidebar widget titles. Essentially, CSS classes group or classify HTML elements<\/strong> that share common traits.<\/p>\n Pseudo-classes are similar to CSS classes because they also apply style rules to elements with shared characteristics<\/strong>. However, while standard classes are user-defined<\/strong> and visible in the source code<\/strong> (e.g., <\/code>), pseudo-classes are applied by user agents (e.g., web browsers)<\/strong> based on the current state of the HTML element.<\/p>\n Pseudo-classes and pseudo-elements can be used in CSS selectors but do not exist in the HTML source code. Instead, they are \u201cinserted\u201d by the user agent under certain conditions for use in style sheets. \u2013 W3C<\/a><\/p>\n The purpose of regular CSS classes<\/strong> is to classify or group elements<\/strong>. Developers group elements based on intended styling, creating classes like \u201cmenu-items,\u201d \u201cbuttons,\u201d or \u201cthumbnails\u201d to ensure consistent design across similar elements. These groupings are based on characteristics defined by the developers<\/strong>.<\/p>\n For example, a developer might use a <\/code> as a thumbnail and classify it with a \u201cthumbnail\u201d class.<\/p>\n However, HTML elements possess inherent characteristics<\/strong> based on their state, position, nature, and interaction with the page and user. These traits are not typically marked in HTML code<\/strong>, but can be targeted with pseudo-classes<\/strong> in CSS. Examples include:<\/p>\n These are the types of characteristics typically addressed by pseudo-classes. To better understand the difference between classes and pseudo-classes, let\u2019s consider using the class You can style these last-child elements with the following CSS:<\/p>\n But what happens when the last element changes? You\u2019ll need to manually update the This hassle of updating classes can be avoided<\/strong> for certain common characteristics. For example, using a predefined CSS offers a variety of pseudo-classes that allow developers to target elements based on specific characteristics that might otherwise be difficult to access. You can find a comprehensive list of standard pseudo-classes<\/a> on MDN.<\/p>\n Dynamic pseudo-classes are applied to HTML elements dynamically<\/strong>, based on the state they transition into due to user interactions<\/strong>. Some examples include State-based pseudo-classes are applied to elements when they are in a specific static state<\/strong>. Common examples include:<\/p>\n:hover<\/a><\/code>, which allows us to style an element when it\u2019s in the hover state<\/strong>, such as when a mouse pointer hovers over it.<\/p>\n
Understanding Pseudo-Classes<\/h4>\n
:<\/code>, like this:
a:hover { ... }<\/code>.<\/p>\n
<\/p>\n
The Role of Pseudo-Classes<\/h4>\n
<\/p>\n
\r\n
\n
.last<\/code> to identify the last elements in various parent containers.<\/p>\n
\r\n
\r\n
\r\n li.last {\r\n text-transform: uppercase;\r\n }\r\n \r\n option.last {\r\n font-style: italic;\r\n }\r\n<\/pre>\n
.last<\/code> class from the previous last element to the new one.<\/p>\n
:last-child<\/code> pseudo-class is highly beneficial. With this, there\u2019s no need to mark the last element<\/strong> in the HTML code, and you can still style it with the following CSS:<\/p>\n
\r\n li:last-child {\r\n text-transform: uppercase;\r\n }\r\n \r\n option:last-child {\r\n font-style: italic;\r\n }\r\n<\/pre>\n
Main Types of Pseudo-Classes<\/h4>\n
1. Dynamic Pseudo-Classes<\/h5>\n
:hover<\/a><\/code>,
:focus<\/a><\/code>,
:link<\/a><\/code>, and
:visited<\/a><\/code>, all of which are commonly used with the
<\/a><\/code> anchor tag.<\/p>\n
\r\n a:visited {\r\n color: #8D20AE;\r\n }\r\n \r\n .button:hover,\r\n .button:focus {\r\n font-weight: bold;\r\n }\r\n<\/pre>\n
2. State-Based Pseudo-Classes<\/h5>\n