Child Theme Problem

I created a child theme of Twenty Fourteen using the wp_enqueue_style() method.

At the moment all my modifications are in the parent style.css (apart from font modifications I have direction: rtl; in the first selector, but excluding body and div.)

The only files in the child theme are style.css and functions.php and both are empty of any modifications.

When I activate the child theme all is well except that the site doesn’t display on iPads – the page is scrunched into a narrow rectangle way over the the right and only the background picture shows. I de-activate the blank child theme and the display problem disappears.

Any suggestions gratefully received.

Thank you.