- Enable RFS
- Add documentation
- Disable doc font size overrides

* Add variables for shades and tints of each major color

* getting-started/theming.md: use a `range`.

Use the built-in utilities instead.

Also, add a warning in _root.scss so that we don't miss it again.

Drop `color()`, `theme-color()` & `gray()` functions  in favor of variables. The functions just called a `map-get()` of a map where just the variables were defined. 

Also the `theme-color-level()` now accepts any color you want instead of only `$theme-colors` colors. The first value now is a variable instead of the `$theme-colors` key.

* Use escape-svg() function

* Update theming.md

Media queries do not support CSS custom properties (CSS variables), so we've had some useless variables lying around since shipping v4. This finally removes them and the associated documentation content that explained the situation.

Fixes #29012.

This allows for the build to fail if a reference isn't found.

No more Ruby dependency and most important more than 10 times less build time (at least on Windows)!

* Prep for v4.3.0

* More updates for v4.3.0.

* rerun to build docs source map

- Move 4.1 docs to 4.2
- Update versions everywhere to 4.1.3 with release script
- Manually bump the shorthand version in package.json
- Add 4.2 to the versions docs page
- Update some redirects
- Fix tests asset URLs
- Bump Nuget and more

* Tweak the accessibility/reduced motion text

include mention of carousel slides, remove the (now inaccurate, as Firefox 63 includes it too) mention that support is limited to Safari/macOS

xref https://github.com/twbs/bootstrap/issues/27525

* Add new callout for reduced motion

* Add variable to control prefers-reduced-motion media query support

* Add callout about prefers-reduced-motion to all components currently using animation which are affected

With the current docs directory setup, I'm making too many mistakes and have to manually address path changes and directory moves on deploy. This makes for a frustrating experience developing locally and shipping releases. With this PR, we're basically back to the same setup from v3—duplicating the dist directory into our docs directory. Not the most ideal, but very straightforward for me as the release manager.

- Only applies to textual inputs and textareas with `.form-control` and selects with `.custom-select`
- Wrap the feedback icons in a Sass variable option, $enable-validation-icons, so folks who theme can disable
- Update docs to summarize styles, mention the icons, include a textarea demo, and add mention of the Sass variable option to the Theming section

* update docs path from docs/4.0/ to docs/4.1/

* bump version to 4.1.0

* Update redirects to work for 4.1 docs move

* Update docs version switcher to include latest and link to 4.0 docs

* re-run dist

* Update package-lock.json

* Update docs-navbar.html

it's ≠ its

* Tell where to find the variables to override

* Be consistent with path to _variables.scss

* Get rid of some 'our' in the doc

Replaced by 'Boostrap's' when relevant

* Add note about insert position of "map-remove"

* Use optional keys instead of required keys

* heading for better linking

* tell folks where to start

* more headings

* required keys section added, closes #25293

* Deprecate hover media query shim and mixins

Fixes #25195.

This never was completed or fully implemented, and the docs are inaccurate as to what browsers are currently affected by this stickied hover problem. This PR aims to update the docs and deprecate the shim from our mixins and only return the pseudo-classes. To reflect the order of these states used elsewhere (e.g., our button styles), I've also updated the order of each within the mixin.

* Mention in docs and variables that it's deprecated