The CSSGroupingRule interface of the CSS Object Model represents any CSS at-rule that contains other rules nested within it.
This interface also inherits properties from CSSRule.
CSSGroupingRule.cssRules Read onlyReturns a CSSRuleList of the CSS rules in the media rule.
This interface also inherits methods from CSSRule.
CSSGroupingRule.deleteRuleDeletes a rule from the style sheet.
CSSGroupingRule.insertRuleInserts a new style rule into the current style sheet.