On Macs and iOS devices, in Safari, a element with a background color generates a gloss over itself. This does not seem to happen in other opera
As mentioned several times here
-webkit-appearance:none;
also removes the arrows, which is not what you want in most cases.
An easy workaround I found is to simply use select2 instead of select. You can re-style a select2 element as well, and most importantly, select2 looks the same on Windows, Android, iOS and Mac.