EpicBlue was originally a [PunBB/FluxBB forum style]. It is now the default forum style at MoonBurnt. The style you're currently viewing is a CSS style of the same name and general apperance as its forum counterpart. The forum style was lightly modded by Ree; the wiki style is her creation.
Here, have an image.
Registered users can enter a custom CSS URL on the Preferences page (at the bottom, just above the footer). Paste
http://www.pokitty.com/squirrel/wiki/EpicBlue.css into Stylesheet URL textbox and click Save. The new style will not take effect until you view another Twine page; for some reason it isn't applied on the yay-you-saved page.