I extended Site Tree with the following code in the page.php file in my mysite/config:
public static $db = array(
'Colour' => 'Text'
The idea is to be able to assign different colours to pages by integrating and assigning css class names to it through the above variable. That works well.
The problem i have is that when i try to call $Colour when i am on any blog page, i cannot access the values. I have tried calling it as $Page.Colour as well but that also does not work.