Background-filter and navbar is broken on mobile version

Here is my site Read-Only: link

Hello on the mobile version below 768px brekapoint my footer doesn’t work properly even tho it has 100% width setup. Besides that the background-filter doesn’t work in custom code or in filters from webflow - sometimes it show on the preview in the webflow editor but never on the actuall browser or mobile phone - why is it like that? In custom code webkit-background-filter is highlited red, so I thought it is the cause - but backgroun filter from webflow doesn’t seem to work properly on mobile nav menu.