There are eight sides like the sketch, it's just a little hard to see the way I have it tilted :)

This is very lovely! I especially like the combination of stripe, plaid, dots and small pattern all in coordinated colors. Also the 7-sided (septagon?) polygon shape for the mid background photo mat is very clever. Of course, it would all mean nothing without the terrific photos! Did I say I like this very much? I do indeed!