prefix properties with "font-"

lib/single-file/single-file-core.js

@@ -625,7 +625,7 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 						stylesheetContent += "@font-face{";
 						let propertiesContent = "";
 						Object.keys(details).forEach(detail => {
-							propertiesContent += detail + ":" + details[detail];
+							propertiesContent += "font-" + detail + ":" + details[detail];
 							propertiesContent += ";";
 						});
 						propertiesContent += "font-family:\"" + name + "\";";