v5.18.0

A big thanks to the 2 contributors who made this release possible.

CSS layers make it easier to override styles by splitting a single style sheet into multiple layers.
To learn more, check out the CSS layers documentation.

@mui/system@5.18.0

• Backport CSS layers from v7 (#46320) @siriwatknp

@mui/material-nextjs@5.18.0

• Backport CSS layers from v7 (#46320) @siriwatknp

Docs

• Ease migration to v5 (#45991) @oliviertassinari
• Add AccordionSummary to the breaking change migration (@siriwatknp) (#45972) @siriwatknp

All contributors of this release in alphabetical order: @oliviertassinari, @siriwatknp