Jump link

Hello Muffin,
sorry, I need to ask a problem I have been working on since days wich I cannot figure out.
Please be so kind and watch this side of my homepage: http://www.axel-steinmueller.de/referenzen
I implemented the Call to Action-Button on the upper right side. It says "Kundenmeinungen" (what my clients say) and when a viewer clicks on it, the site should jump down to the section in gray, where you can see the company icons.
I tried it with link="/#referenzen" target=""......connected with the custom id /#refernzen  the gray section.
But if I click on the button it leads to http://www.axel-steinmueller.de/ (the home-site) where I have a similar link. (Service and Angebot).
This button works.
I tried several other options. But no luck.
It would be great if you can help me.
Thank you.
Best wishes
Axel