CSS Nesting Syntax Not Working

[CaperAsDev]

Hi,

This is my first time reporting an issue, so I hope this is the right place to do it.

Issue:
After including compress in my project, I noticed that some styles using CSS nesting syntax stopped working. I tried setting CSS to false in the integration config, but it didn't resolve the issue. Eventually, I removed the integration, and the styles worked correctly again.

This is just an example of some of the nesting styles that did't work.

[lewisakura]

I recently encountered this issue myself and found (after some brainstorming with Astro support <3) that the csso compressor seems to be way too out of date to understand what nested rules are. LightningCSS seems to be fine however, so you can just disable csso and force LightningCSS and things should work properly:

compress({
	CSS: {
		csso: false,
		lightningcss: {
			minify: true,
		},
	},
}),