First check that the light bulbs are dimmable.
Create a rule with the desired light bulb and select Power On/Off > Fade In/Fade Out and the desired time period.
During this time, the light bulb will fade in until it reaches the set brightness or fades out until it is turned off.
If a period of 10 minutes is selected, fade-in begins 10 minutes before the set rule.
Example: If the rule is set to 07:00 and the fade-in is set to 15 minutes, the fade-in begins at 06:45 and is finished at 07:00.