Creating a "line" before the Signature Block (and/or change in color for the area)

I am newer and just going through my customizations.  I would like to add a line to separate my Signature Block from the main area of my Emails.  Is this possible?  Can we also make the background of the Signature Block Area a different color than the rest of the email?

Yes, that is possible in the HTML view. Right-click in the signature window and select  change source. Enter the following HTML code:

James Bond

Tel: 007

On the following website you will find a good tutorial on HTML and CSS