Demystifying CSS Pseudo Elements: Use and Practical Examples

Pseudo-elements in CSS are a powerful tool for styling certain parts of an HTML document without needing to add additional elements in the markup structure. Despite their usefulness, they are often overlooked, which can deprive us of elegant and efficient solutions when bringing web designs to life.

What Are Pseudoelements?

Pseudo-elements are keywords that we add to selectors in cascading style sheets (CSS) to style specific parts of an element. They are not actual HTML elements, but rather "ghosts" or extensions that allow us to style subcomponents of an element that are not represented as objects in the Document Object Model (DOM).

Among the best known we find ::before y ::despues de, which allow us to insert content before or after the main content of an element. Others like ::first-line y ::first-letter They are useful for styling the first line or letter of a paragraph, respectively.

Utility and Benefits of Pseudoelements

The magic of pseudo-elements lies in their ability to create visual effects without overloading the HTML with new tags just for styling. We can add decorative borders, shadows, or even manipulate the presentation of fragments of text in a paragraph without altering the semantics of the document.

The main use of pseudo-elements is stylistic-decorative, but they can also improve accessibility by allowing us to adapt the presentation of the content without modifying its structure.

Examples of Common Use of Pseudoelements

1. Decorative Boxes with ::before y ::despues de:
   We can create decorative frames or dividers by adding borders or shapes before and after the content of an element.

2. Styling the First Letter with ::first-letter:
   It is perfect for giving a touch of elegance to texts, like the sections of an old book.

3. Improve First Line Readability with ::first-line:
   Modify the first line of a paragraph to highlight it, changing its font or color.

4. Icons or Decorative Elements without Images:
   Before font-based icons were popular, they were used ::before y ::despues de to insert decorative images.

Syntax and Rules of Pseudoelements

The syntax is simple. The double colon is used :: followed by the name of the pseudo-element, and is placed just after the selector to which we want to apply it. For example, to style the first letter of a paragraph, we would use p::first-letter.

Difference between Pseudoelements and Pseudo-classes

While pseudo-elements select and style a specific part of an element, pseudo-classes determine the state of an element. For example, :hover affects the style of a link when you mouse over it.

Limitations and Rules of Good Practice

It is important to know that pseudo-elements have their limitations. Not all browsers have the same level of support for certain pseudo-elements, and in general, they cannot be used to add real, meaningful content to the page, since that is not their semantic purpose.

Additionally, they can only be applied to elements containing other elements or text, which means that ::before y ::despues de They don't work with elements like img o input that are self-contained.

Conclusions and recommendations

Pseudoelements are essential allies for any web designer or developer looking for clean and maintainable code. Its ability to decorate and enhance the presentation without altering the underlying HTML is a virtue that facilitates efficiency in the work of styling a web page.

For those who wish to delve deeper into the use of CSS and web best practices, I invite you to visit nelkodev.com, where you will find valuable resources for developers and designers of all levels. And if you have any specific questions or queries, do not hesitate to contact me through https://nelkodev.com/contacto so that together we can explore the wonders of modern web development.