Custom CSS Support: Media queries

[scruffian]

In #73959 we added support for custom CSS to individual blocks. It would be great if this also supported media queries. At the moment if I add:

  @media (min-width: 1024px) {
    & {
      grid-template-columns: repeat(2, 1fr); /* 2 columns at 1024px+ */
    }
  }

This is what gets outputted:

:root :where(.wp-custom-css-af3a99c3@media (min-width: 1024px) ){}:root :where(.wp-custom-css-af3a99c3){grid-template-columns: repeat(2, 1fr); }

I would expect this:

@media (min-width: 1024px) ){ :root :where(.wp-custom-css-af3a99c3){grid-template-columns: repeat(2, 1fr); }