Short description of the problem:
The last form element has a wider bottom border than the previous ones. Also the borders touching the right side of the screen.

What behaviour are you expecting?
It is not clear if this was by design for Ionic to stand out. But according to the Material Design guidelines at https://material.google.com/components/text-fields.html#text-fields-full-width-text-field it shows all bottom borders are of the same width.

Which Ionic Version? 2.x