Android CSS issue: fantom white overlay (zoomable and touchable) in every browser very strange

I made a website and check it in every browser. All browsers is ok but Android is not.

After ~30% of website height there is white overlay up to end of page.

This bug displays in every Android browser, like Chrome or stock browser app. I check that with BrowserStack.

First of all, website is here.

Screenshots that display bug:

screenshot 1

screenshot 2

I made video to show this bug: https://youtu.be/UbXp7o-v64Y

Actually, what I'm trying but that is not worked:

• Remove overflow-x
• Set z-index 9999 for html and body
• Turn off all scripts
• Comment some sections in HTML

I know that bug is in style.css because if I remove <link> bug is disappear (with all styles of course)

How I can check what is this? I have not any debug tool on android. Any ideas.