diff --git a/src/web/styles.css b/src/web/styles.css
index 51d4851..11009dc 100644
--- a/src/web/styles.css
+++ b/src/web/styles.css
@@ -292,6 +292,7 @@ p {
 .harbor-mode-swap path {
   transform-box: fill-box;
   transform-origin: center;
+  transition: transform 420ms cubic-bezier(0.16, 1, 0.3, 1);
 }
 
 .harbor-mode-swap .is-connect {