How wide is the shade?
The widest part of the lampshade measures 11.2''.
Does the provided rgb light bulb work with alexa devices?
Yes it does work with Alexa devices. The app you need to download to control the rgb bulb is called TuyaSmart if you would like to look into it further.
What material is the lampshade?
The lampshade is the material of frosted plastic. Lightweight drop proof and soft lighting.
Can the bulb be replaced?
Of course, you can choose cold or warm light bulbs by yourself to account personal preference or application environment(bulb included). Please pay attention to the type of bulbs, it's E26 lamp holder, no more than 60W (allow dimming).