[BUG] blog gallery tiles have too much height

[gabalafou]

The following two comments describe and set the stage for this issue.

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I'm not so big a fan of the fix for the gallery card sizing. For card rows where both cards have less content, it leaves a lot of whitespace:

Originally posted by @bskinn in #746 (review)

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Changes probably have to happen right around here?

Might have to switch to rendering these as a series of flex containers, each containing two posts, where each container responsively switches from flex-col on narrow screens to flex-row on wide screens?

Originally posted by @bskinn in #759 (comment)