Pricing page graphics

Internal review, round 1. Holding this before it goes to sign-off because two things would come straight back:

• The three plan columns use three different corner radii. Pick one, 8px matches the rest of the site.
• "Most popular" badge sits outside the card on mobile at 375px.

Not blocking: I would drop the drop shadow entirely, but that is a preference, not a change request. Ignore it if you disagree.