protected override void ReplaceWith(ICssRule rule)
{
base.ReplaceWith(rule);
var newRule = rule as CSSMediaRule;
_media.Import(newRule._media);
}
protected override void ReplaceWith(ICssRule rule)
{
var newRule = rule as CssImportRule;
_href = newRule._href;
_media.Import(newRule._media);
_styleSheet = newRule._styleSheet;
}