This is "Persian blue", based on the article about the banner itself.  Since I haven't read the story, I'm open to suggestions.  TR (talk) 17:52, May 4, 2014 (UTC)

Sounds right to me since the body of the banner is blue. I don't recall any specific adjectives to the color so Persian is good. ML4E (talk) 18:03, May 4, 2014 (UTC)
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