Arduino source for controlling a small light used for putting a child to sleep and indicating when it's a suitable time to get up.
There are two buttons. One triggers "sleep mode", which lights all six lights red and gradually fades them over a short period.
The circuit has a DS3231 real-time clock, which is used for "waking up" mode. This lights up LEDs yellow sequentially, then performs a "rainbow" for a few seconds, and finally lights up all six LEDs bright green, indicating that it's OK to get up now.