We add a new `use_responsive_design` helper, for pages to opt into this
new CSS—mostly just because like… it's *worse* to apply these styles
for pages that don't expect it 😅
And then, I fix up a couple things on the item page (including in the
general items layout) to match!
I'm doing this because the species face picker layout is going to want
some responsive awareness, and I want to be doing that from the start!
TNT requested that we figure out ways to connect the dots between
people's intentions on DTI to their purchases in the NC Mall.
But rather than just slam ad links everywhere, our plan is to design an
actually useful feature about it: the "Item Getting Guide". It'll break
down items by how you can actually get them (NP economy, NC Mall,
retired NC, Dyeworks, etc), and we're planning some cute actions you
can take, like shortcuts for getting them onto trade wishlists or into
your NC Mall cart.
This is just a little demo version of the page, just breaking down
items specified in the URL into NC/NP/PB! Later we'll do more granular
breakdown than this, with more info and actions—and we'll also like,
link to it at all, which isn't the case yet! (The main way we expect
people to get here is by a "Get these items" button we'll add to the
outfit editor, but there might be other paths, too.)
