Help needed: Wordpress Template crashed after Wordpress update

Our school runs a Wordpress theme we purchased in 2013 (Cleanspace Business, author mad_dog).
It always worked out great so far but with the latest WordPress update (5.6) the theme doesn’t have the white site background but a transparent scrolling site (I don’t know how to express it better).
The address is

Who can help fix the problem and restore the original page layout?

Thanks for any help!


Please contact the author to get support:

You can also try to install this plugin to fix the issue (once installed, go to its settings and set jQuery version to Legacy):

Thank you so much! The jQuery plugin advice solved the problem.

Hello ,

My advice is to put some better template which supports new versions off WP and have regular updates. Also your SSL certificate is not setup good. Half sites is http and other https.