[WIP] remove 1px gray line in bg2 + use scale(1.12) for minimized error

[bsansouci]

It seems like chrome does some rounding here and it makes a grey line appear at the top of the card. It's more visible on non-retina monitors. This plays with the rounding and makes the issue much less visible.

Before:

After:

[bsansouci]

It doesn't affect safari. But it does affect the size of the card (of course), your call if this is acceptable. Still looking for a better solution, don't merge