diff --git a/web/templates/index.html b/web/templates/index.html
index 96187c2..14dcf57 100644
--- a/web/templates/index.html
+++ b/web/templates/index.html
@@ -149,6 +149,7 @@
       cursor: pointer;
       transition: background 0.12s, color 0.12s;
       line-height: 1;
+      outline: none;
     }
 
     .mode-btn + .mode-btn {