diff --git a/buffer.go b/buffer.go
index 10b6271..4160e87 100644
--- a/buffer.go
+++ b/buffer.go
@@ -24,6 +24,8 @@ const (
 	StyleNormal     Style = iota
 	StyleBold       Style = iota >> 1
 	StyleItalic
+	StyleUnderline
+	StyleHighlight
 	StyleBoldItalic Style = StyleBold | StyleItalic
 )