Add CSS class to region div in page.tpl based on custom field selection

I've created a page.tpl with a few regions that I will be using for a landing page. I've also created a custom bean block type with a select list field that I would like to use to add a css class for the specific region.

For example I have the values: red, black, blue in the custom block type. When selected (red) I want to be able to print that value in the regions main div container based on that specific block type.

This is my first time using Drupal and would be open to any suggestions if there's an easier way. Any help much appreciated!