Word 2007 Page Borders with Shadow: change color?

I have a legacy document with a page border in one color and a shadow that’s black. I’ve been asked to make the shadow blue.

I can change the color of the page border itself (ribbon – page layout, page border), and I can add or remove the black shadow, but I do not – so far – see a way to change the color of the shadow itself. Is this possible?

If necessary, I could fake it by making a text box the right size…the text box tool has a “Shadow Effects” pulldown under Text Box Tools that lets me change the shadow color. It’s conceivable that the Page Border also has a pulldown somewhere to change the color of the shadow, but I don’t see a context-sensitive “Page Border Tools” anywhere so far.