In simple mode the color of the second hand changes from standard blue to a greenish yellow whenever the minute hand and the hour hand are at the same position (at 00:00, 01:05, 02:10, 03:16, 04:21, 05:27, 06:32, 07:38, 08:43, 09:49, 10:54 and 11:59) and stays greenish yellow for the full minute. After that minute (= when the minute hand and the hour hand have different positions again) the second hand becomes blue again.
In simple mode the color of the second hand changes from standard blue to a greenish yellow whenever the minute hand and the hour hand are at the same position (at 00:00, 01:05, 02:10, 03:16, 04:21, 05:27, 06:32, 07:38, 08:43, 09:49, 10:54 and 11:59) and stays greenish yellow for the full minute. After that minute (= when the minute hand and the hour hand have different positions again) the second hand becomes blue again.