Replace phyiscal properties (top/bottom/left/right) with logical
properties (start/end) that can be used in non-LTR contexts (e.g.,
content in Arabic or Hebrew).
Based on the CSS Logical Properties and Values Level 1 specification,
currently an Editor's Draft [1].
Referencing MDN, all major browsers except Internet Explorer support the
margin, padding, and border properties.
[1]: https://drafts.csswg.org/css-logical/
Signed-off-by: Tim Crawford <crawfxrd@gmail.com>
Allows for special styles to call them out since they're different than
normal text and different than code. They can make use of styles they
inherit for font style and weight.
Notes on changes:
- Added new CSS variables for reused elements
- The font-* rules are separate for each aspect so that they can inherit
bold/italic/etc
Closes https://github.com/rust-lang/mdBook/issues/1813
* ui: improve menu folding
Fold/unfold the menu bar just by the amount of scroll, not by its
full width
* refactor: use a variable for the menu bar height
* Fix menu scroll jittering, remove hover folding smoothness
Rewrite it to use `position:` `sticky` and `relative` instead
of continuous programmatic position changes
On-hover folding-unfolding transition removal is a side-effect
This replaces the only use of px for font-sizes by setting up a base
rem size on the root element in a way that is easy to calculate (1 rem =
10px) and scaling up according to browser settings.
