> just change the "import css" file at the top and have completely different styles.
I'm afraid I don't understand the goal here. This is excatly what classless frameworks like Simple.css are doing, and classless is imo a much better solution than us all agreeing onto standard variable names.
It's not just because these are "drop-in" files that like these libraries can not be extended or have some variables overridden.
For example, TFA says that simple.css uses a variable called "accent" to determine the color of links and buttons. If other styles adopt the same name, then you could just define the "color palette" in one place and have each library working as totally different "design language".
I'm afraid I don't understand the goal here. This is excatly what classless frameworks like Simple.css are doing, and classless is imo a much better solution than us all agreeing onto standard variable names.