Vertical time zones

["firehorse888uk" <firehorse888uk@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Hi,

Has anyone got code to plot a background colour for timezones.

For example, 
between 8:30 and 13:30 to plot a background of blue
between 13:30 and 20:00 to plot a background of green
between 00:00 and 08:00 to plot a background of red

Thanks
Alan