CSS decoded ::before and ::after

What is a Pseudo Element in CSS?

A CSS Pseudo Element is a keyword added to a selector that lets you style a specific part of the selected element(s). For example, ::first-line can be used to style the first line of a paragraph, ::before can be used to prepend an element and style it as well, etc.

The main utility of the Pseudo Element is for cosmetic purpose only.

In CSS3 the Pseudo Elements are represented by ::<pseudo-element>, even though the CSS2 syntax :<pseudo-element> still works on most browsers for the Pseudo Elements that were available in CSS2.

What is the use of ::before and ::after?

In CSS, ::before and ::after creates pseudo-elements that is the prepended and appended to the selected element respectively.

How do I use ::before and ::after in my website?

One really important thing to keep in mind while using ::before and ::after is to set content property in the CSS

selector::before{
  /* without content the pseudo-elements will not work */
  content: "";
}

After adding the content, you can style them just like any other element