Birthday invitation for a 6 year old boy

Thsi is an invitation I made for my son's 6th birthday party. He is gaga over guitars and he really likes blue. So this is what I came up with. A bit of a different idea. I find boy invitations a bit difficult as you don't want them to look like they were created for a girl. If you have any ideas or inspiration for boys invitations, I would love to see them.