Theme doesn't show up on the homepage

Hello everyone

I am busy setting up new blog, which will be my first WordPress blog. I have customized the Twenty-Eleven theme to my liking. When I’m logged in as the admin and go to my site, the theme shows up normally.

However, when I’m not logged in, it shows the default theme instead of the one I edited. Is there any way to fix this, or does it just take some time to get adjusted?

It might just be my computer, but you can never be too sure. Can anyone verify if the theme shows up correctly, and if it doesn’t help me correct the problem?

This is my website, the theme should be black with a custom header, nothing too fancy but still.
maikelmichielssponsoring.com

Thanks in advance,
Maikel Michiels