initial

The initial CSS keyword applies the initial value of a property to an element. It is allowed on every CSS property and causes the element for which it is specified to use the initial value of the property.

Example

<!DOCTYPE html>
<html>
    <head>
        <style>
            /* make second-level headers green */
            /* give headers a green border */
            h2 {
                border: medium solid green
            }
            
            /* but make those in the sidebar use the value 
			of the "color" property */ 
			#sidebar h2 {
                border-color: initial;
            }
        </style>
    </head>
    <body>
        <p style="color:red">
            this text is red<em style="color:initial">
            this text is in the initial color (e.g. black)
            </em>
            this is red again
        </p>
    </body>
</html>