Reference to :root in cerulean _bootswatch.scss

[ctipper]

You probably want to take a look at this in light of bootstrap #37377: Import root in bootstrap-utilities
dist/cerulean/_bootswatch.scss#L9

:root {
   color-scheme: light;
}

I am not an expert I am just reporting an issue I found trying to build with grunt on my machine. Also I am curious when the time comes how dark themes are going to affect the build procedure in 5.3.0?

[ctipper]

Due to way sass compiles imports this will replace bootstrap :root resulting in bad rendering of pages. This was only apparent after the PR was merged into bootstrap.