feat: rename dark/high-contrast themes to palettes (#29149)

Issue number: Internal

---------

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issue. -->

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etc). Submit multiple pull requests if needed. -->

## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

Ionic Framework currently plans to offer dark and high contrast "themes"
in v8. However this naming nomenclature conflicts with a significant new
feature that the team is working on towards v9+.

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Migrates previous dark and high contrast "themes" to "palettes"
- Updates test infrastructure to import from the new stylesheet
locations

## Does this introduce a breaking change?

- [x] Yes
- [ ] No

<!--
  If this introduces a breaking change:
1. Describe the impact and migration path for existing applications
below.
  2. Update the BREAKING.md file with the breaking change.
3. Add "BREAKING CHANGE: [...]" to the commit description when merging.
See
https://github.com/ionic-team/ionic-framework/blob/main/.github/CONTRIBUTING.md#footer
for more information.
-->

Developers that have updated to the Ionic v8 beta and have implemented
the dark and high contrast themes, will need to update the import path:

```diff
-@import '@ionic/angular/css/themes/dark.always.css';
+@import '@ionic/angular/css/palettes/dark.always.css';
```


## Other information

<!-- Any other information that is important to this PR such as
screenshots of how the component looks before and after the change. -->

Blocked by: #29148.
Review that first.

Documentation PR: ionic-team/ionic-docs#3521

---------

Co-authored-by: Liam DeBeasi <[email protected]>

Author: sean-perkins

BREAKING.md

@@ -14,7 +14,7 @@ This is a comprehensive list of the breaking changes introduced in the major ver
 ## Version 8.x
 
 - [Browser and Platform Support](#version-8x-browser-platform-support)
-- [Dark Theme](#version-8x-dark-theme)
+- [Dark Mode](#version-8x-dark-mode)
 - [Global Styles](#version-8x-global-styles)
 - [Components](#version-8x-components)
   - [Button](#version-8x-button)
@@ -60,9 +60,9 @@ This section details the desktop browser, JavaScript framework, and mobile platf
 | iOS      | 15+                    |
 | Android  | 5.1+ with Chromium 89+ |
 
-<h2 id="version-8x-dark-theme">Dark Theme</h2>
+<h2 id="version-8x-dark-mode">Dark Mode</h2>
 
-In previous versions, it was recommended to define the dark theme in the following way:
+In previous versions, it was recommended to define the dark palette in the following way:
 
 ```css
 @media (prefers-color-scheme: dark) {
@@ -80,15 +80,15 @@ In previous versions, it was recommended to define the dark theme in the followi
 }
 ```
 
-In Ionic Framework version 8, the dark theme is being distributed via css files that can be imported. Below is an example of importing a dark theme file in Angular:
+In Ionic Framework version 8, the dark palette is being distributed via css files that can be imported. Below is an example of importing a dark palette file in Angular:
 
 ```css
-/* @import '@ionic/angular/css/themes/dark.always.css'; */
-/* @import "@ionic/angular/css/themes/dark.class.css"; */
-@import "@ionic/angular/css/themes/dark.system.css";
+/* @import '@ionic/angular/css/palettes/dark.always.css'; */
+/* @import "@ionic/angular/css/palettes/dark.class.css"; */
+@import "@ionic/angular/css/palettes/dark.system.css";
 ```
 
-By importing the `dark.system.css` file, the dark theme variables will be defined like the following:
+By importing the `dark.system.css` file, the dark palette variables will be defined like the following:
 
 ```css
 @media (prefers-color-scheme: dark) {
@@ -106,11 +106,11 @@ By importing the `dark.system.css` file, the dark theme variables will be define
 }
 ```
 
-Notice that the dark theme is now applied to the `:root` selector instead of the `body` selector. The [`:root`](https://developer.mozilla.org/en-US/docs/Web/CSS/:root) selector represents the `<html>` element and is identical to the selector `html`, except that its specificity is higher.
+Notice that the dark palette is now applied to the `:root` selector instead of the `body` selector. The [`:root`](https://developer.mozilla.org/en-US/docs/Web/CSS/:root) selector represents the `<html>` element and is identical to the selector `html`, except that its specificity is higher.
 
-While migrating to include the new dark theme files is unlikely to cause breaking changes, these new selectors can lead to unexpected overrides if custom CSS variables are being set on the `body` element. We recommend updating any instances where global application variables are set to target the `:root` selector instead.
+While migrating to include the new dark palette files is unlikely to cause breaking changes, these new selectors can lead to unexpected overrides if custom CSS variables are being set on the `body` element. We recommend updating any instances where global application variables are set to target the `:root` selector instead.
 
-For more information on the new dark theme files, refer to the [Dark Mode documentation](https://ionicframework.com/docs/theming/dark-mode).
+For more information on the new dark palette files, refer to the [Dark Mode documentation](https://ionicframework.com/docs/theming/dark-mode).
 
 <h2 id="version-8x-global-styles">Global Styles</h2>
 

core/src/css/palettes/dark.always.scss

@@ -0,0 +1,13 @@
+@import "./dark";
+
+:root {
+  @include dark-base-palette();
+}
+
+:root.ios {
+  @include dark-ios-palette();
+}
+
+:root.md {
+  @include dark-md-palette();
+}

core/src/css/palettes/dark.class.scss

@@ -0,0 +1,13 @@
+@import "./dark";
+
+.ion-palette-dark {
+  @include dark-base-palette();
+}
+
+.ion-palette-dark.ios {
+  @include dark-ios-palette();
+}
+
+.ion-palette-dark.md {
+  @include dark-md-palette();
+}

core/src/css/themes/dark.scss renamed to core/src/css/palettes/dark.scss

@@ -1,61 +1,53 @@
-@mixin dark-base-theme() {
+@mixin dark-base-palette() {
   & {
     --ion-color-primary: #4d8dff;
     --ion-color-primary-rgb: 77, 141, 255;
     --ion-color-primary-contrast: #000000;
     --ion-color-primary-contrast-rgb: 0, 0, 0;
     --ion-color-primary-shade: #447ce0;
     --ion-color-primary-tint: #5f98ff;
-
     --ion-color-secondary: #62bdff;
     --ion-color-secondary-rgb: 98, 189, 255;
     --ion-color-secondary-contrast: #000000;
     --ion-color-secondary-contrast-rgb: 0, 0, 0;
     --ion-color-secondary-shade: #56a6e0;
     --ion-color-secondary-tint: #72c4ff;
-
     --ion-color-tertiary: #8482fb;
     --ion-color-tertiary-rgb: 132, 130, 251;
     --ion-color-tertiary-contrast: #000000;
     --ion-color-tertiary-contrast-rgb: 0, 0, 0;
     --ion-color-tertiary-shade: #7472dd;
     --ion-color-tertiary-tint: #908ffb;
-
     --ion-color-success: #2dd55b;
     --ion-color-success-rgb: 45, 213, 91;
     --ion-color-success-contrast: #000000;
     --ion-color-success-contrast-rgb: 0, 0, 0;
     --ion-color-success-shade: #28bb50;
     --ion-color-success-tint: #42d96b;
-
     --ion-color-warning: #ffce31;
     --ion-color-warning-rgb: 255, 206, 49;
     --ion-color-warning-contrast: #000000;
     --ion-color-warning-contrast-rgb: 0, 0, 0;
     --ion-color-warning-shade: #e0b52b;
     --ion-color-warning-tint: #ffd346;
-
     --ion-color-danger: #f56570;
     --ion-color-danger-rgb: 245, 101, 112;
     --ion-color-danger-contrast: #000000;
     --ion-color-danger-contrast-rgb: 0, 0, 0;
     --ion-color-danger-shade: #d85963;
     --ion-color-danger-tint: #f6747e;
-    
     --ion-color-dark: #f4f5f8;
     --ion-color-dark-rgb: 244, 245, 248;
     --ion-color-dark-contrast: #000000;
     --ion-color-dark-contrast-rgb: 0, 0, 0;
     --ion-color-dark-shade: #d7d8da;
     --ion-color-dark-tint: #f5f6f9;
-    
     --ion-color-medium: #989aa2;
     --ion-color-medium-rgb: 152, 154, 162;
     --ion-color-medium-contrast: #000000;
     --ion-color-medium-contrast-rgb: 0, 0, 0;
     --ion-color-medium-shade: #86888f;
     --ion-color-medium-tint: #a2a4ab;
-    
     --ion-color-light: #222428;
     --ion-color-light-rgb: 34, 36, 40;
     --ion-color-light-contrast: #ffffff;
@@ -65,14 +57,12 @@
   }
 }
 
-@mixin dark-ios-theme() {
+@mixin dark-ios-palette() {
   & {
     --ion-background-color: #000000;
     --ion-background-color-rgb: 0, 0, 0;
-
     --ion-text-color: #ffffff;
     --ion-text-color-rgb: 255, 255, 255;
-
     --ion-background-color-step-50: #0d0d0d;
     --ion-background-color-step-100: #1a1a1a;
     --ion-background-color-step-150: #262626;
@@ -92,7 +82,6 @@
     --ion-background-color-step-850: #d9d9d9;
     --ion-background-color-step-900: #e6e6e6;
     --ion-background-color-step-950: #f2f2f2;
-
     --ion-text-color-step-50: #f2f2f2;
     --ion-text-color-step-100: #e6e6e6;
     --ion-text-color-step-150: #d9d9d9;
@@ -112,7 +101,6 @@
     --ion-text-color-step-850: #262626;
     --ion-text-color-step-900: #1a1a1a;
     --ion-text-color-step-950: #0d0d0d;
-
     --ion-item-background: #000000;
     --ion-card-background: #1c1c1d;
   }
@@ -124,16 +112,13 @@
   }
 }
 
-@mixin dark-md-theme() {
+@mixin dark-md-palette() {
   & {
     --ion-background-color: #121212;
     --ion-background-color-rgb: 18, 18, 18;
-
     --ion-text-color: #ffffff;
     --ion-text-color-rgb: 255, 255, 255;
-
     --ion-border-color: #222222;
-
     --ion-background-color-step-50: #1e1e1e;
     --ion-background-color-step-100: #2a2a2a;
     --ion-background-color-step-150: #363636;
@@ -153,7 +138,6 @@
     --ion-background-color-step-850: #dbdbdb;
     --ion-background-color-step-900: #e7e7e7;
     --ion-background-color-step-950: #f3f3f3;
-
     --ion-text-color-step-50: #f3f3f3;
     --ion-text-color-step-100: #e7e7e7;
     --ion-text-color-step-150: #dbdbdb;
@@ -173,7 +157,6 @@
     --ion-text-color-step-850: #363636;
     --ion-text-color-step-900: #2a2a2a;
     --ion-text-color-step-950: #1e1e1e;
-
     --ion-item-background: #1e1e1e;
     --ion-toolbar-background: #1f1f1f;
     --ion-tab-bar-background: #1f1f1f;

core/src/css/themes/dark.system.scss renamed to core/src/css/palettes/dark.system.scss

@@ -2,14 +2,14 @@
 
 @media (prefers-color-scheme: dark) {
   :root {
-    @include dark-base-theme();
+    @include dark-base-palette();
   }
 
   :root.ios {
-    @include dark-ios-theme();
+    @include dark-ios-palette();
   }
 
   :root.md {
-    @include dark-md-theme();
+    @include dark-md-palette();
   }
 }

core/src/css/palettes/high-contrast-dark.always.scss

@@ -0,0 +1,13 @@
+@import "./high-contrast-dark";
+
+:root {
+  @include high-contrast-dark-base-palette();
+}
+
+:root.ios {
+  @include high-contrast-dark-ios-palette();
+}
+
+:root.md {
+  @include high-contrast-dark-md-palette();
+}

core/src/css/palettes/high-contrast-dark.class.scss

@@ -0,0 +1,13 @@
+@import "./high-contrast-dark";
+
+.ion-palette-high-contrast.ion-palette-dark {
+  @include high-contrast-dark-base-palette();
+}
+
+.ion-palette-high-contrast.ion-palette-dark.ios {
+  @include high-contrast-dark-ios-palette();
+}
+
+.ion-palette-high-contrast.ion-palette-dark.md {
+  @include high-contrast-dark-md-palette();
+}

core/src/css/themes/high-contrast-dark.scss renamed to core/src/css/palettes/high-contrast-dark.scss

@@ -93,8 +93,10 @@ $lightest-text-color: $text-color;
 /// as opposed to setting everything in :root
 // so any high contrast dark styles override the standard
 /// contrast dark styles.
-@mixin high-contrast-dark-base-theme() {
+@mixin high-contrast-dark-base-palette() {
   & {
+    --ion-placeholder-opacity: 0.8;
+
     @each $color-name, $value in $colors {
       --ion-color-#{$color-name}: #{map.get($value, base)};
       --ion-color-#{$color-name}-rgb: #{color-to-rgb-list(map.get($value, base))};
@@ -104,27 +106,23 @@ $lightest-text-color: $text-color;
       --ion-color-#{$color-name}-tint: #{map.get($value, tint)};
     }
 
-    --ion-placeholder-opacity: 0.8;
   }
 }
 
-@mixin high-contrast-dark-ios-theme() {
+@mixin high-contrast-dark-ios-palette() {
+  $background-color: #000000;
+  
   & {
-    $background-color: #000000;
-
     --ion-background-color: #{$background-color};
     --ion-background-color-rgb: #{color-to-rgb-list($background-color)};
-
     --ion-text-color: #{$text-color};
     --ion-text-color-rgb: #{color-to-rgb-list($text-color)};
-
     --ion-item-background: #000000;
     --ion-card-background: #1c1c1d;
 
     /// Only the item borders should increase in contrast
     /// Borders for elements like toolbars should remain the same
     --ion-item-border-color: var(--ion-background-color-step-400);
-
     --ion-text-color-step-50: #{mix($darkest-text-color, $lightest-text-color, 5%)};
     --ion-text-color-step-100: #{mix($darkest-text-color, $lightest-text-color, 10%)};
     --ion-text-color-step-150: #{mix($darkest-text-color, $lightest-text-color, 15%)};
@@ -144,7 +142,6 @@ $lightest-text-color: $text-color;
     --ion-text-color-step-850: #{mix($darkest-text-color, $lightest-text-color, 85%)};
     --ion-text-color-step-900: #{mix($darkest-text-color, $lightest-text-color, 90%)};
     --ion-text-color-step-950: #{mix($darkest-text-color, $lightest-text-color, 95%)};
-
     --ion-background-color-step-50: #{mix($text-color, $background-color, 5%)};
     --ion-background-color-step-100: #{mix($text-color, $background-color, 10%)};
     --ion-background-color-step-150: #{mix($text-color, $background-color, 15%)};
@@ -176,18 +173,15 @@ $lightest-text-color: $text-color;
   }
 }
 
-@mixin high-contrast-dark-md-theme() {
+@mixin high-contrast-dark-md-palette() {
+  $background-color: #121212;
+  
   & {
-    $background-color: #121212;
-
     --ion-background-color: #{$background-color};
     --ion-background-color-rgb: #{color-to-rgb-list($background-color)};
-
     --ion-text-color: #{$text-color};
     --ion-text-color-rgb: #{color-to-rgb-list($text-color)};
-
     --ion-border-color: #222222;
-
     --ion-item-background: #1e1e1e;
     --ion-toolbar-background: #1f1f1f;
     --ion-tab-bar-background: #1f1f1f;
@@ -196,7 +190,6 @@ $lightest-text-color: $text-color;
     /// Only the item borders should increase in contrast
     /// Borders for elements like toolbars should remain the same
     --ion-item-border-color: var(--ion-background-color-step-400);
-
     --ion-text-color-step-50: #{mix($darkest-text-color, $lightest-text-color, 5%)};
     --ion-text-color-step-100: #{mix($darkest-text-color, $lightest-text-color, 10%)};
     --ion-text-color-step-150: #{mix($darkest-text-color, $lightest-text-color, 15%)};
@@ -216,7 +209,6 @@ $lightest-text-color: $text-color;
     --ion-text-color-step-850: #{mix($darkest-text-color, $lightest-text-color, 85%)};
     --ion-text-color-step-900: #{mix($darkest-text-color, $lightest-text-color, 90%)};
     --ion-text-color-step-950: #{mix($darkest-text-color, $lightest-text-color, 95%)};
-
     --ion-background-color-step-50: #{mix($text-color, $background-color, 5%)};
     --ion-background-color-step-100: #{mix($text-color, $background-color, 10%)};
     --ion-background-color-step-150: #{mix($text-color, $background-color, 15%)};

core/src/css/themes/high-contrast-dark.system.scss renamed to core/src/css/palettes/high-contrast-dark.system.scss

@@ -2,14 +2,14 @@
 
 @media (prefers-contrast: more) and (prefers-color-scheme: dark) {
   :root {
-    @include high-contrast-dark-base-theme();
+    @include high-contrast-dark-base-palette();
   }
 
   :root.ios {
-    @include high-contrast-dark-ios-theme();
+    @include high-contrast-dark-ios-palette();
   }
 
   :root.md {
-    @include high-contrast-dark-md-theme();
+    @include high-contrast-dark-md-palette();
   }
 }

core/src/css/palettes/high-contrast.always.scss

@@ -0,0 +1,9 @@
+@import "./high-contrast";
+
+:root {
+  @include high-contrast-light-base-palette();
+}
+
+:root.md {
+  @include high-contrast-light-md-palette();
+}