ECOM-811 design and layout changes

@wedaly @stephensanchez @rlucioni here are the style and text updates. Unfortunately I had to use teh dreaded !important in my Sass to override some ridiculously specific selectors, but after the A/B test we can clean this up by removing the legacy styles.
If possible, please break onto separate lines. It's very hard to read like this.

"we will review over the next (x) hours" - this fragment is missing an object, which may be hard for ESL people to parse. I would recommend something like, "photos. We will review your photos over the next {num_hours} hours."

`ungettext` is required here, because of the `num_hours` variable. Other languages have varying pluralization forms, so we have to use ngettext even when we think we don't (eg because it will always be >1 and English only has two plural forms. But ... this gets wicked complicated in other languages).

"If there is a problem with any of the items" - what does "the items" refer to? This needs clarity. Don't you just mean "your photos"? Or "your identification materials"? Be more clear here.

Finally, to make this sentence easier, I'd recommend doing two separate translation strings. Do an ungettext call for the first part ("Thank you ... hours."), and a regular gettext call for the remaining ("If there is a problem...").