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Remove offset support for vertical grid since % top/bottom margin is based on width (therefore doesn't work).

Add files via upload

Remove offset support for vertical grid since % top/bottom margin is based on width (therefore doesn't work).

Add files via upload

Bug fix: min-width changed to 1px from 0 to fix cells not wrapping
Improvement: use :where() to lower default values and reset's specificity to 0.
Optimization: changed *:nth-child() to :nth-child as * is not required.

Update README.md

Formatting fix.