addRule method
Implementation
void addRule(CSSRule rule, { required String? baseHref }) {
rule.position = _lastPosition++;
if (rule is CSSStyleRule) {
for (final selector in rule.selectorGroup.selectors) {
findBestRuleSetAndAdd(selector, rule);
}
} else if (rule is CSSKeyframesRule) {
keyframesRules[rule.name] = rule;
} else if (rule is CSSFontFaceRule) {
CSSFontFace.resolveFontFaceRules(rule, ownerDocument.contextId!, baseHref);
} else {
assert(false, 'Unsupported rule type: ${rule.runtimeType}');
}
}