The parsable textual representation of the rule. This reflects the
current state of the rule and not its initial value.
Throws:
-
DOMException - SYNTAX_ERR: Raised if the specified CSS string value has a syntax
error and is unparsable.
INVALID_MODIFICATION_ERR: Raised if the specified CSS string
value represents a different type of rule than the current one.
HIERARCHY_REQUEST_ERR: Raised if the rule cannot be inserted at
this point in the style sheet.
NO_MODIFICATION_ALLOWED_ERR: Raised if the rule is readonly.