} else if (condition instanceof ContentCondition) {
// Unimplemented in CSS2?
} else if (condition instanceof LangCondition) {
LangCondition c = (LangCondition) condition;
return ":lang(" + c.getLang() + ")";
} else if (condition instanceof NegativeCondition) {
// Unimplemented in CSS2?
} else if (condition instanceof PositionalCondition) {
// Unimplemented in CSS2?