The initial value given in the summary of the definition of each CSS property has different meaning for inherited and non-inherited properties.
For inherited properties, the initial value is used, for the root element only, when no value is specified for the element.
For non-inherited properties the initial value is used, for any element, when no value is specified for the element.
The initial
keyword has been added in CSS3 to allow authors to explicitly specify this initial value.
initial
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https://developer.mozilla.org/en-US/docs/Web/CSS/initial_value