What is the symbol for a pseudo element?

The symbol of a pseudo element is a double colon "::" to distinguish it from the pseudo class ":". However, some older versions of browsers still support the use of a single colon ":" to represent pseudo elements. , this is for backward compatibility.

# Operating system for this tutorial: Windows 10 system, Dell G3 computer.

The symbol for a pseudo-element is a double colon (::).

In CSS2, the symbol of pseudo-element is a single colon (:). In CSS3, it is stipulated to use double colon (::) to distinguish pseudo-elements and pseudo-classes so that they can be distinguished from pseudo-classes (: ) to make a distinction. However, some older browsers still support the use of a single colon (:) to represent pseudo-elements for backward compatibility.

In CSS3, in addition to ::before and ::after, some new pseudo-elements are also added, such as ::first-line, ::first-letter, ::selection, etc., they all use Double colon (::) to represent.

It should be noted that some browsers do not support double colons (::) to represent pseudo elements. Therefore, when writing CSS code, it is best to use double colons (::) to represent pseudo elements to ensure that the code compatibility.

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