Add dark mode support (#35857)

* Add dark mode to docs

* Minor fix: missing space indentation

* Minor fix: revert utilities/z-index added-in modification

* Remove prev: and next: from doc because extracted to another PR

* Use .bg-body-tertiary in all Utilities > Overflow examples

* fix example

* Fix up spacing examples

* Update box-shadow Sass variables and utilities to auto-adjust to color modes

* Remove unused docs class

* Refactor form styles to use CSS variable for background images on .form-check and .form-switch

* Fix docs selector

* Rename shortcut for clarity

* Heading consistency

* Reintroduce missing 4th grid item in Utilities > Spacing example

* Fix bundlewatch

* .bd-callout* rendering is OK so removing comments in the code

* Update scss/_utilities.scss

Co-authored-by: Julien Déramond <[email protected]>

* Fix gutters example styling

* Fix text colors on background utils docs

* redesign and fix up position marker example, which doesn't show nicely in darkmode but at least isn't broken

* fix some color utils examples

* Deprecate mixin notice

* Deprecate notice for list-group-item-variant() mixin

* Revamp new link CSS vars

* Use map-keys in some each Sass files

* Remove list-group-item-variant mixin ref in sass loop desc

* Display CSS vars scoped to our built-in dark mode

* Revert previous commit

* Fix list group variant link

* Fix typo

* Remove imports of alert/list-group mixins in scss/_mixins.scss

* Small formatting + comments removal in scss/_content.scss

* Fix alert links colors

* fix dropdown border-radius mixin

* fix link color and underline again, this time using CSS var override for color var and fallback value for the underline

* fix colors on docs navbar for dark mode

* remove two changes

* missing ref

* another link underline fix, just use sass vars for link decoration for now

* missing color bg docs, plus move dropdown override to scss

* more changes from review

* fix some examples, drop unused docs navbar styles, update docs navbar color mode to use mixin

* Few fixes around type

- Restored CSS variable for color on headings, this time with a fallback value
- In conjunction, restored and wrapped the default CSS var with a null value check
- Split headings and paragraphs docs in Reboot, elaborated on them

* Restyle custom details > summary element in docs

* Rewrite some migration docs

* fix form checks

* Fix up some navbar styling, tweak docs callout

* Fix select images, mostly for validation styling

* Clean up some migration notes, document some new form control CSS vars, mention new variables-dark in sass docs

* Update site/content/docs/5.2/components/scrollspy.md

Co-authored-by: Julien Déramond <[email protected]>

* Apply suggestions from code review

Co-authored-by: Julien Déramond <[email protected]>

* mention form control css vars in migration guide

* Tweak grid and flex docs background examples

* clarify some docs

* fix some more things

Co-authored-by: Julien Déramond <[email protected]>
Co-authored-by: Julien Déramond <[email protected]>

1 files changed, 8 insertions, 11 deletions

diff --git a/scss/_alert.scss b/scss/_alert.scss
index c8bc91b42..8647851b1 100644
--- a/scss/_alert.scss
+++ b/scss/_alert.scss
@@ -12,6 +12,7 @@
   --#{$prefix}alert-border-color: transparent;
   --#{$prefix}alert-border: #{$alert-border-width} solid var(--#{$prefix}alert-border-color);
   --#{$prefix}alert-border-radius: #{$alert-border-radius};
+  --#{$prefix}alert-link-color: inherit;
   // scss-docs-end alert-css-vars
 
   position: relative;
@@ -32,6 +33,7 @@
 // Provide class for links that match alerts
 .alert-link {
   font-weight: $alert-link-font-weight;
+  color: var(--#{$prefix}alert-link-color);
 }
 
 
@@ -54,18 +56,13 @@
 
 
 // scss-docs-start alert-modifiers
-// Generate contextual modifier classes for colorizing the alert.
-
-@each $state, $value in $theme-colors {
-  $alert-background: shift-color($value, $alert-bg-scale);
-  $alert-border: shift-color($value, $alert-border-scale);
-  $alert-color: shift-color($value, $alert-color-scale);
-
-  @if (contrast-ratio($alert-background, $alert-color) < $min-contrast-ratio) {
-    $alert-color: mix($value, color-contrast($alert-background), abs($alert-color-scale));
-  }
+// Generate contextual modifier classes for colorizing the alert
+@each $state in map-keys($theme-colors) {
   .alert-#{$state} {
-    @include alert-variant($alert-background, $alert-border, $alert-color);
+    --#{$prefix}alert-color: var(--#{$prefix}#{$state}-text);
+    --#{$prefix}alert-bg: var(--#{$prefix}#{$state}-bg-subtle);
+    --#{$prefix}alert-border-color: var(--#{$prefix}#{$state}-border-subtle);
+    --#{$prefix}alert-link-color: var(--#{$prefix}#{$state}-text);
   }
 }
 // scss-docs-end alert-modifiers