Transparency of main content layer in University template

I asked this in a topic before for 'staekhouse template' and I think Oscar helped me out:
[url]https://www.gavick.com/forums/steak-house-joomla3/transparency-of-main-content-layer-41807.html?p=208668&hilit=Transparency%20of%20main%20content%20layer#p208668
[/url]

and it worked fine for

http://54404758.swh.strato-hosting.eu/hochzeitsautomieten.de/index.php/de/#specials

But as I switched to university template in between:
How and where can i set this in university?

Could you please post an url to your site?

http://university.kever-events.nl/index.php/de/

thanks in advance

Could you please mark on a screenshot which part that is currently white you would like to make semi transparent?