- Changes the wrapping label to a div so we can style the label instead of another element while also supporting form validation.
- Fixes form validation styles for custom file input (closes #24831).
- Updates docs with validation styles (also adding example feedback text while I was there) and new how it works section.

* Remove unnecessary float

- since parent btn-group is displayed as inline-flex, the child elements are placed left to right by default.

* Cleanup of reset rounded corners

- Remove `border-radius :0` since it is enough by each reset of left and right side
- A `.dropdown-toggle` selector should not be used for reset rounded corner since it does not have border-radius property. Instead use .dropdown-toggle as negation pseudo-class.

* Fix input group border radius issue (#25075)

* Remove migration note

- All buttons In input group do not have to be the same element now.

* lint

Fixes #25016 which noticed a .thead-light and border-color of the .table-border are the same color.

Adds some additional context on `.form-group` usage

Matches browser default inputs and swaps some max-width properties for a regular width

Update our browserslist.

* Add `last 1 major version` and `>= 1%`.
* Add Firefox.

Firefox v38 is older than the ESR, so basically replace ESR with v38.

* adds a hover state to the button element on the backrgound color utitility

* Adjust z-index to fix hover/focus overlaps

* Updated Link For Getting started Page

* Change URL scheme of previous commit

From http to https

* Restyle code element, clean up variables

- Removes the padding and background-color
- Changes the color to a brand color ()
- Add new variables to kbd element styles to account for removing the code ones
- Remove overrides that were needed previously

* only break between words, and override it in the pre

* make file inputs 100% wide

* scope custom file changes in input group for sizing

* shorter button labels for responsive

* narrower cards

* button was too wide

* downsize

* fewer links in pagination

* redo cell text

* improve overflow docs