Add the feature to add custom properties

[max-norin]

You can use PostCSS to add custom properties. This plugin can't check custom properties. For example size properties in postcss-short. You also don't have any logical CSS properties: margin-block, margin-block-start, margin-block-end, margin-inline, margin-inline-start, margin-inline-end, margin-start, margin-end and etc.

[darwintantuco]

will check this out when I have the time

[darwintantuco]

Interesting! first time seeing postcss-short and I agree, it's a perfect use case of adding custom properties.

[darwintantuco]

I'm not familiar with logical CSS properties, will check it out.

[darwintantuco]

apologies for the radio silence, totally forget about this

initial PRs:

• Support css logical properties #39
• Support custom properties #40