We have a bug on iPad where an unwanted drop shadow is displayed on the email subscribe field. iPad also changes (or ignores) the padding on the submit button.
It displays correctly (as below) on all other devices:
Remember too that on ipad, the horizontal orientation is showing the Desktop Viewport in Webflow and when switching the orientation to portrait, the Tablet viewport in Webflow is shown, do you have any shadow stylings for the field on regular desktop view?
Is your iPad having all latest iOS updates loaded?