diff --git a/index.less b/index.less
index 0ed9c80..a8471d7 100644
--- a/index.less
+++ b/index.less
@@ -11,6 +11,7 @@
 @import 'languages/gfm';
 @import 'languages/ini';
 @import 'languages/java';
+@import 'languages/javascript';
 @import 'languages/json';
 @import 'languages/ruby';
 @import 'languages/python';
diff --git a/styles/languages/javascript.less b/styles/languages/javascript.less
new file mode 100644
index 0000000..38921b7
--- /dev/null
+++ b/styles/languages/javascript.less
@@ -0,0 +1,15 @@
+.source.js {
+    // keywords are definded in https://github.com/atom/language-javascript/blob/master/grammars/javascript.cson
+    // search "instanceof" for location
+    .keyword.operator {
+        &.delete,
+        &.in,
+        &.of,
+        &.instanceof,
+        &.new,
+        &.typeof,
+        &.void {
+            color: @syntax-color-keyword;
+        }
+    }
+}