diff --git a/test/mode_test.js b/test/mode_test.js
index 2e16eba0eedab9049509a515c6fa46d4f267f1e1..0aed50f7dc0ebe2b94e4de667a01eec5558cfaae 100644
--- a/test/mode_test.js
+++ b/test/mode_test.js
@@ -170,7 +170,7 @@
     for (var i = 0; i < output.length; ++i) {
       var style = output[i].style, val = output[i].text;
       s +=
-      '<td class="mt-token"' + (i == diffAt * 2 ? " style='background: pink'" : "") + '>' +
+      '<td class="mt-token"' + (i == diffAt ? " style='background: pink'" : "") + '>' +
         '<span class="cm-' + esc(String(style)) + '">' +
         esc(val.replace(/ /g,'\xb7')) +  // · MIDDLE DOT
         '</span>' +