This change has two pieces:
First, the tips in the review dialog weren't showing correctly because

somewhere along the line I lost the change that actually imports the CSS

for slideshow elements into the common bundle.
Second, the previous, next, and close buttons were all somewhat hard to

hit, and were missing some attributes needed for accessibility.

Verified that the tips UI worked correctly.
Checked the hit boxes and a11y attributes for the various buttons in

  the box.