diff --git a/index.html b/index.html
index 5ea8a6d..4c1dede 100644
--- a/index.html
+++ b/index.html
@@ -30,6 +30,10 @@
             transition: all 500ms;
         }
 
+        .out {
+            stroke: lightgray;
+        }
+
         .node.out {
             fill: orange;
             transform: translate(8px, 0px);