Fedoras are a do, but bucket hats are a don't. Colors such as charcoal, navy, brown and black are in — bright ones like red and yellow are out. Patterns are cool, as long as they are small and subtle, and denim works as long as it's not light-wash.

These may sound like decrees from the glossy pages of a fashion magazine, but in fact, they are missives from Starbucks' new employee dress code. The coffee giant had announced earlier this month that it was going to loosen up its requirements for what baristas should wear in its restaurants, promising that the new rules would allow for more "self-expression." Now, the restaurant chain released a 15-page lookbook to show employees (and the rest of us) what that actually means.

It's a fascinating document, and not just because of the somewhat mind-boggling level of precision and detail about what's okay to wear. It also reveals something about the kind of workplace Starbucks is trying to be and the kind of vibe it is trying to create for its customers.

Starbucks employees will continue to wear the green or black aprons that you're used to seeing when you hit up their stores. But lots of subtle changes are coming to what workers can wear underneath. Previously, they could only wear black, white and khaki clothing; now, the palette is more varied and includes other subdued colors such as blue, gray and brown. And they are now permitted to wear patterned shirts, though there are lots of particulars about what makes for an acceptable pattern. Here's a screenshot from the lookbook: