Update style.css

style.css

@@ -143,7 +143,7 @@ body {
     }
 
     #swap-btn {
-        transform: rotate(90deg); /* Rotate arrow to vertical */
+        transform: rotate(180deg); /* Rotate arrow to vertical */
         width: 50px; /* Ensure button size stays the same */
         height: 50px;
     }