Logical border width properties don't retain override order

[AndrewLeedham]

I seem to have run in to a bug via cssnano, which I have traced back to here. I have logical border width properties overriding a reset of the border width, but the order of the override is not being retained. So given:

div {
    background: grey;
    border-width: 0;
    border-top-width: 1px;
    border-inline-start-width: 1px;
 }

I am getting:

div {
    background: grey;
    border-inline-start-width: 1px;
    border-width: 0;
    border-top-width: 1px;
}

This means the border-inline-start-width is ignored because the border-width overrides it.

I created a minimal repro with the above code to demonstrate the issue: https://runkit.com/embed/zdr51an9amcj.

[Siilwyn]

Great find!