5.12.3 The :before and :after pseudo-elements

Chapter 5 - Selectors - 5.12.3 The :before and :after pseudo-elements

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After and before pseudo-elements
After and before pseudo-element allows inserted text after or before a given element.
First-letter pseudo-element with :before pseudo-element
When the :first-letter pseudo-element is combined with :before, :first-letter applies to the generated text of :before.