diff --git a/lib/ace/theme/textmate.js b/lib/ace/theme/textmate.js
index 76eb0673..41a3c31e 100644
--- a/lib/ace/theme/textmate.js
+++ b/lib/ace/theme/textmate.js
@@ -101,8 +101,8 @@ exports.cssText = ".ace-tm .ace_editor {\
 }\
 \
 .ace-tm .ace_line .ace_invalid {\
-  background-color: rgb(153, 0, 0);\
-  color: white;\
+  background-color: rgba(255, 0, 0, 0.1);\
+  color: red;\
 }\
 \
 .ace-tm .ace_line .ace_support.ace_function {\