Whats up with the CSS syntax since the move from LESS/SCSS? Is it valid CSS?

[KingWebsites]

Hi, I'm trying to use the CSS modularly (in a Gulp build) but it seems that the CSS files are actually still formatted as LESS after this change 118ec66 .

Is the idea that CSS Nesting has relatively good support in modern browsers so there's no need for the LESS files to be modified? So ampersands are being kept in the code, e.g. &.swiper-horizontal (in pagination.css)?

These nested selectors are all in swiper-bundle.min.css so they are not currently being processed as normal LESS/SCSS would have been.

In the pagination.css (line #80) you also have the ampersand after the selector: button&. Is this a one-off bug?

This isn't a criticism, I'd just like to know the thinking behind this as I'm having trouble injecting this into my build with my SCSS pre-processor to create a single CSS file for my site.

Thanks.