I have a unique problem which I hope someone can help fix.
I have tweaked my WordPress header on CSS, canceling the background color, so that the background image can be seen instead (it is a white .png image with transparency at the bottom edge so that there is a pattern rather than a straight line at its bottom border).
see http://m.piccolo.co.il or https://piccolo.co.il (2 different websites).
the header's background-image has position: fixed (#masthead)
This works fine when you scroll down on a browser such as Chrome, or Explorer. However, when I scroll on IOS mobile, at some point the header's background-image disappears, leaving only the toggle bar and logo fixed.
screenshot from IOS10 - Iphone SE
This is the header's CSS:
background-size: 100% 100px;
background-attachment: fixed !important;
Any suggestions would be great, I am getting very frustrated with this.