This is a compromise between the old color when selected and when not
selected. It makes the border a little easier to see while still being
subtle.
(imported from commit 7177d8f688af3de15f3e309d6a9c7c248acb1db4)
Since we no longer change the selected message's background color, it
doesn't make sense for these other colors to still change when the
message is selected.
(imported from commit a7c387e7d390b7f2973dc6bd3168651d88880139)
The width setting was unintentional, and it interferes with
the inline-block settings for the image and bot info.
(imported from commit 741c82829efed00b6d47badcf14b26223b47a7a9)