Walk on rule content tokens to return a dict of properties.

        This is pretty naive and will choke/fail on everything that is more
        evolved than simple ``ident(string):value(string)``

        Arguments:
            rule (tinycss2.ast.QualifiedRule): Qualified rule object as
                returned by  tinycss2.

        Returns:
            dict: Dictionnary of retrieved variables and properties.

def digest_content(self, rule):
        """
        Walk on rule content tokens to return a dict of properties.

        This is pretty naive and will choke/fail on everything that is more
        evolved than simple ``ident(string):value(string)``

        Arguments:
            rule (tinycss2.ast.QualifiedRule): Qualified rule object as
                returned by  tinycss2.

        Returns:
            dict: Dictionnary of retrieved variables and properties.
        """
        data = OrderedDict()

        current_key = None

        for token in rule.content:
            # Assume first identity token is the property name
            if token.type == 'ident':
                # Ignore starting '-' from css variables
                name = token.value
                if name.startswith('-'):
                    name = name[1:]

                current_key = name
                data[current_key] = None

            # Assume first following string token is the property value.
            if token.type == 'string':
                data[current_key] = token.value

        return data