This commit makes the dark mode preview feel a little more interactive
and it also pulls some duplicated code into one file so that people like
me aren't stumped when they are looking at the wrong page!

v0.2.5 release branch

Bump stylelint-config-primer from 6.0.0 to 7.0.0

Bump @primer/css from 12.2.3 to 12.3.1

Bumps [@primer/css](https://github.com/primer/css) from 12.2.3 to 12.3.1.
- [Release notes](https://github.com/primer/css/releases)
- [Changelog](https://github.com/primer/css/blob/master/CHANGELOG.md)
- [Commits](https://github.com/primer/css/compare/v12.2.3...v12.3.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [stylelint-config-primer](https://github.com/primer/stylelint-config-primer) from 6.0.0 to 7.0.0.
- [Release notes](https://github.com/primer/stylelint-config-primer/releases)
- [Changelog](https://github.com/primer/stylelint-config-primer/blob/master/CHANGELOG.md)
- [Commits](https://github.com/primer/stylelint-config-primer/compare/v6.0.0...v7.0.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

v0.2.4 release branch

Bump stylelint-config-primer from 3.0.1 to 6.0.0

Bump stylelint from 9.10.1 to 10.0.1

Add SEO and 'lang' param for `_config`

Import custom Sass variable overrides before default variables are defined

Remove unnecessary console.log()

Explain how to use theme locally with GitHub Pages

Bumps [stylelint](https://github.com/stylelint/stylelint) from 9.10.1 to 10.0.1.
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/master/CHANGELOG.md)
- [Commits](https://github.com/stylelint/stylelint/compare/9.10.1...10.0.1

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Bumps [stylelint-config-primer](https://github.com/primer/stylelint-config-primer) from 3.0.1 to 6.0.0.
- [Release notes](https://github.com/primer/stylelint-config-primer/releases)
- [Changelog](https://github.com/primer/stylelint-config-primer/blob/master/CHANGELOG.md)
- [Commits](https://github.com/primer/stylelint-config-primer/commits/v6.0.0

)

Signed-off-by: dependabot[bot] <support@dependabot.com>