Previously deprecated in v4.x, this clears out the now unused Sass option and removes some unused mixins. Arguably we could remove more, but I like the hover-focus mixin and we make extensive use of it across the project.
* 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.
These were using `z-index: 2` to "Place active items above their
siblings for proper border styling". However, using `z-index: 1` is
sufficient for accomplishing that goal.
In input-group, there were also three `z-index: 3` rules for the
hover/focus/active states. I reduced these to `z-index: 2` since they
just needed to be "one more than normal" (i.e. one more than what is now
`z-index: 1` after my changes).
These changes can be verified by viewing the documentation pages for
Button group, Input group, List group, and Pagination before and after
this commit and observing that the active elements are still "above"
their siblings, so their borders look correct.
- Fixes#20298 for vertical button group spacing
- Fixes#20784 for horizontal (default) button group spacing
- Alternate fix to #20823 which only applied a fix for vertical button groups
- Really we didn't need to do any of that strip units stuff to generate six new variables, two for each button size
- Using sibling selectors, we can target those split button dropdown toggles using the .dropdown-toggle-split class, and adjust padding and margin as needed
- Now, we nuke the margin-left from the ::after generated caret and tighten up the padding so that those split toggles don't look huge next to their main button
