diff --git a/tensorboard/webapp/widgets/line_chart_v2/sub_view/line_chart_interactive_view.scss b/tensorboard/webapp/widgets/line_chart_v2/sub_view/line_chart_interactive_view.scss
index e70af81bb5..d1c9a59bd0 100644
--- a/tensorboard/webapp/widgets/line_chart_v2/sub_view/line_chart_interactive_view.scss
+++ b/tensorboard/webapp/widgets/line_chart_v2/sub_view/line_chart_interactive_view.scss
@@ -100,7 +100,9 @@ th {
   right: 0;
   top: 10px;
   transition: opacity 0.5s;
+  z-index: 1;
 }
+
 .instruction-content {
   background: rgba(0, 0, 0, 0.6);
   border-radius: 5px;