[Script -Color light when I write text ?]

~ Hi, I'm a newbie in this "scripts" things. 
I would like to know if a script can be made for a small object (a small lamp)
that is turned on using a clear blue light 
only when I am writing a message to the "general chat" and then after stopping writing the light goes out.
If you can do the script or help me do it, I thank you, greetings and thanks for responding.

pd; Im from Argentina. 
Si me lo explica alguien en español mucho mejor
jeje .. Gracias !! :D

// Ark0th //