PC 1.7.8.0 Modal windows not working

[MirooZ]

Some facts: I'm on PS 1.7.8.0 upgraded from 1.6.0.9 in a few steps (via 1.6.1.24, 1.7.6.x). PHP: 7.4.20, MySQL: 5.6.25. 

 

Yep, I did some mods, mainly for forcing PS to work properly. I modified theme css mainly. 

 

The problem I have is related to modal windows - none of them is displayed. That causes confusion in my head as I cannot find any reason why it's not working. Due to not displaying modal window after adding product to the basket the number of items in the basket is not being refreshed. 

 

I need fresh look to find out what is wrong. 

Would you please help me.

 

The webpage can be reached at http://www.mokkamint.pl

 

Thanks 

MirooZ

custom.css

Edited October 21, 2021 by MirooZ (see edit history)