drag and drop not working on safari because background moves

I have a web page that has drag and drop features.

This works fine in Chome and Firefox, but not in Safari
because the background moves when trying to drag an element

As per answers elsewhere, I have put in the following in the css sheet

Code Block 
html, body {
  overflow:hidden;
}

This works fine when the website is called from the url bar
in safari

However, when exactly the same page is called from the home screen, the background is no longer locked

In my index file I also have ;

Code Block 
<meta name="apple-mobile-web-app-capable" content="yes">

I have also changed:

Code Block 
<meta name="viewport" content="width=device-width, initial-scale=1.0">

to

Code Block 
<meta name="viewport"
content="width=device-width, height=device-height,
initial-scale=1.0">

But the height=device-height does not seem to have any
effect – so the page still scrolls

Any ideas how to keep the page locked in Safari on IoS from the home screen?

Thanks