We're switching entirely to npm for distributing missing.css. Prior versions
will be kept on the.missing.style, but its use is deprecated and our
release notes pages will not link to it. Instead, use one of many npm
CDNs (unpkg, jsdelivr, etc.) or install the package via npm.
If a colored background is applied to an <aside> using the .bg class, it
will have horizontal padding added to prevent the text hitting the edge of
the background.
Colorways were fiddled with.
Fixed: Asides now have vertical margins equal to --gap.