With the Magic Button, I can choose between three different lighting scenes in which the light becomes warmer when dimmed down. What colour temperature ranges are these and how can I set them?

We call these three colour modes Clear Light, Golden Light and Sunset Orange.
When dimmed, the colour temperatures in these ranges change:

Clear light 2700K-2200K*
Golden light 2300K-1500K*
Sunset orange 2000K-1300K*

*These are not measured values, but the emotional classification of the perceived colour temperatures.

The smaller Magic Button on the underside of the lamp allows you to choose between the three colour modes.
Use the larger Power button on the underside of the lamp to switch Salt off completely.