Why is the `content` Property Essential for Styling `:before` and `:after` Pseudo-elements?

Understanding the Necessity of the 'content' Property for :before and :after Pseudo-Elements

:before and :after pseudo-elements allow us to insert generated content before or after an element. To function, these pseudo-elements require the use of the 'content' property.

Why 'content' is Essential

According to the W3C specification, the 'content' property plays a crucial role in defining the content generated by these pseudo-elements. When 'content' is set to 'none,' which is its initial value, no content is generated. Therefore, no displayed content is available to be styled.

The Styling Connection

Applying styles to ::before and ::after pseudo-elements only affects the display of the generated content. Without specifying the 'content' property, there is no content present for the styles to apply to.

Avoiding Redundancy

To avoid repeatedly setting 'content:'';' for multiple :before and :after pseudo-elements, a CSS global style can be utilized:

::before, ::after {
    content:'';
}

This approach ensures that all generated content for :before and :after pseudo-elements will have a default value of an empty string, allowing styles to be applied accordingly.

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