Used to set a property value and priority within this declaration
block.
setProperty
permits to modify a property or add a
new one in the declaration block. Any call to this method may modify
the order of properties in the
item
method.
Parameters:
-
propertyName - The name of the CSS property. See the CSS
property index.
-
value - The new value of the property.
-
priority - The new priority of the property (e.g.
"important"
) or the empty string if none.
Throws:
-
DOMException - SYNTAX_ERR: Raised if the specified value has a syntax error and is
unparsable.
NO_MODIFICATION_ALLOWED_ERR: Raised if this declaration is
readonly or the property is readonly.