Enable get phone cta for Spain bug 878871

This PR includes:

* Enables get-a-phone cta buttons for Spain (**es**)
* CSS styles for newsletter signup and get phone content when **JS is disabled**
* Minor CSS style amends for locale content with long strings (testing against `es-ES` specifically).

Things to test:

* Get phone cta buttons should now appear when `geo.mozilla.org` returns country code `es`.
* Newsletter and get-phone content looks ok with JS disabled at all CSS breakpoints.
* Newsletter and get-phone modal content still displays as intended, with **JS enabled**.