remove invalid rules

lib/single-file/modules/css-rules-minifier.js

@@ -77,7 +77,7 @@ this.cssRulesMinifier = this.cssRulesMinifier || (() => {
 				} else if (cssRuleData.type == "Rule") {
 					const ruleInfo = mediaInfo.rules.get(cssRuleData);
 					const pseudoSelectors = mediaInfo.pseudoRules.get(cssRuleData);
-					if (!ruleInfo && !pseudoSelectors) {
+					if ((!ruleInfo && !pseudoSelectors)) {
 						removedCssRules.push(cssRule);
 					} else if (ruleInfo) {
 						processRuleInfo(cssRuleData, ruleInfo, pseudoSelectors);
@@ -86,6 +86,10 @@ this.cssRulesMinifier = this.cssRulesMinifier || (() => {
 						}
 					}
 				}
+			} else {
+				if (!cssRuleData || cssRuleData.type == "Raw" || (cssRuleData.type == "Rule" && (!cssRuleData.prelude || cssRuleData.prelude.type == "Raw"))) {
+					removedCssRules.push(cssRule);
+				}
 			}
 		}
 		removedCssRules.forEach(cssRule => cssRules.remove(cssRule));