jquery – Disables, hides, or removes the native IOS drop-down menu – Using select2

I've initialized select2 and created a style that works great on FF, Chrome, IE on PC and Android … It also works on IOS, but when I click or touch categories to launch the drop-down / select menu, I see the menu select for a fraction of a second (curiously, the elements are not displayed, but lines, see the image below) …

I've added some code that hides select2 until it's loaded, but it does happen anyway.

I have also deleted all my custom CSS, without success.

Is there a way to disable, hide, or delete the IOS drop-down menu?

You will find attached an image of what I see on an iPad. It only appears for a fraction of a second, but it is very visible. My test page is http://mediaworldwide.co.uk/perfect-storm/ams-test. -site / case studies / …. Thank you
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