@layer extensions, components;
@layer extensions.one,,invalid-layer-names..foo;

@layer extensions {
	@layer one, two
}

:is(:mobile(extensions)) {
	color: yellow;
}

:is(:tablet(components)) {
	color: green;
}

:is(:desktop(unlayered)) {
	color: blue;
}

:is(:dark(layouts)) {
	color: pink;
}

:is(:light(extensions-two)) {
	color: red;
}
