fix(button): activated outline button in toolbar no longer blends into background on MD dark mode (#29216)

Issue number: N/A

---------

<!-- Please do not submit updates to dependencies unless it fixes an
issue. -->

<!-- Please try to limit your pull request to one type (bugfix, feature,
etc). Submit multiple pull requests if needed. -->

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

When using an outline-style button in a toolbar on `md` dark mode, the
activated style causes the button to become invisible.

Steps to repro in `main`:
1. Update the `css-variables` themes test to use the latest dark theme
styles (at least for v7) by replacing the contents of [this
file](https://github.com/ionic-team/ionic-framework/blob/main/core/src/themes/test/css-variables/css/dark.css)
with the [styles from the
docs](https://ionicframework.com/docs/theming/dark-mode#ionic-dark-theme).
2. Host the project locally and navigate to the test at
`themes/test/css-variables/index.html`.
3. Switch to dark mode within the page. Note that the activated outline
button isn't visible:

![image](https://github.com/ionic-team/ionic-framework/assets/90629384/fae1009f-4962-4e6b-b710-42deec083e84)


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

- Button styles corrected. The colors were correct for `ios` mode, but
had to be flipped for `md`, so I pulled the relevant styles into the
mode-specific stylesheets.
- CSS variables test has also been updated to use the same dark mode CSS
as in [the
docs](https://ionicframework.com/docs/theming/dark-mode#ionic-dark-theme),
as per the repro steps above. Let me know if you would rather this be
split into a separate PR.

Changes to the toolbar test were split into a separate PR to keep this
one clean and ensure the screenshot changes can be reviewed more
effectively: https://github.com/ionic-team/ionic-framework/pull/29231

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

<!--
  If this introduces a breaking change:
1. Describe the impact and migration path for existing applications
below.
  5. Update the BREAKING.md file with the breaking change.
6. 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.
-->


## Other information

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

---------

Co-authored-by: ionitron <hi@ionicframework.com>

core/src/components/button/button.ios.scss

@@ -212,3 +212,12 @@
 :host(.button-solid.ion-color.ion-activated) .button-native::after {
   background: #{current-color(shade)};
 }
+
+
+// Activated Button in Toolbar
+// --------------------------------------------------
+
+:host(.button-outline.ion-activated.in-toolbar:not(.ion-color):not(.in-toolbar-color)) .button-native {
+  background: var(--ion-toolbar-color, var(--color));
+  color: #{var(--ion-toolbar-background, var(--background), ion-color(primary, contrast))};
+}

core/src/components/button/button.md.scss

@@ -160,3 +160,12 @@
     background: #{current-color(base)};
   }
 }
+
+
+// Activated Button in Toolbar
+// --------------------------------------------------
+
+:host(.button-outline.ion-activated.in-toolbar:not(.ion-color):not(.in-toolbar-color)) .button-native {
+  background: var(--ion-toolbar-background, var(--color));
+  color: #{var(--ion-toolbar-color, var(--background), ion-color(primary, contrast))};
+}

core/src/components/button/button.scss

@@ -331,11 +331,3 @@ ion-ripple-effect {
   background: #{var(--ion-toolbar-color, var(--background))};
   color: #{var(--ion-toolbar-background, var(--color))};
 }
-
-// Activated Button in Toolbar
-// --------------------------------------------------
-
-:host(.button-outline.ion-activated.in-toolbar:not(.ion-color):not(.in-toolbar-color)) .button-native {
-  background: var(--ion-toolbar-color, var(--color));
-  color: #{var(--ion-toolbar-background, var(--background), ion-color(primary, contrast))};
-}

core/src/themes/test/css-variables/css/dark.css

@@ -1,74 +1,84 @@
-:root {
+/*
+ * Dark Colors
+ * -------------------------------------------
+ */
+
+body {
   --ion-color-primary: #428cff;
-  --ion-color-primary-rgb: 66,140,255;
+  --ion-color-primary-rgb: 66, 140, 255;
   --ion-color-primary-contrast: #ffffff;
-  --ion-color-primary-contrast-rgb: 255,255,255;
+  --ion-color-primary-contrast-rgb: 255, 255, 255;
   --ion-color-primary-shade: #3a7be0;
   --ion-color-primary-tint: #5598ff;
 
   --ion-color-secondary: #50c8ff;
-  --ion-color-secondary-rgb: 80,200,255;
+  --ion-color-secondary-rgb: 80, 200, 255;
   --ion-color-secondary-contrast: #ffffff;
-  --ion-color-secondary-contrast-rgb: 255,255,255;
+  --ion-color-secondary-contrast-rgb: 255, 255, 255;
   --ion-color-secondary-shade: #46b0e0;
   --ion-color-secondary-tint: #62ceff;
 
   --ion-color-tertiary: #6a64ff;
-  --ion-color-tertiary-rgb: 106,100,255;
+  --ion-color-tertiary-rgb: 106, 100, 255;
   --ion-color-tertiary-contrast: #ffffff;
-  --ion-color-tertiary-contrast-rgb: 255,255,255;
+  --ion-color-tertiary-contrast-rgb: 255, 255, 255;
   --ion-color-tertiary-shade: #5d58e0;
   --ion-color-tertiary-tint: #7974ff;
 
   --ion-color-success: #2fdf75;
-  --ion-color-success-rgb: 47,223,117;
+  --ion-color-success-rgb: 47, 223, 117;
   --ion-color-success-contrast: #000000;
-  --ion-color-success-contrast-rgb: 0,0,0;
+  --ion-color-success-contrast-rgb: 0, 0, 0;
   --ion-color-success-shade: #29c467;
   --ion-color-success-tint: #44e283;
 
   --ion-color-warning: #ffd534;
-  --ion-color-warning-rgb: 255,213,52;
+  --ion-color-warning-rgb: 255, 213, 52;
   --ion-color-warning-contrast: #000000;
-  --ion-color-warning-contrast-rgb: 0,0,0;
+  --ion-color-warning-contrast-rgb: 0, 0, 0;
   --ion-color-warning-shade: #e0bb2e;
   --ion-color-warning-tint: #ffd948;
 
   --ion-color-danger: #ff4961;
-  --ion-color-danger-rgb: 255,73,97;
+  --ion-color-danger-rgb: 255, 73, 97;
   --ion-color-danger-contrast: #ffffff;
-  --ion-color-danger-contrast-rgb: 255,255,255;
+  --ion-color-danger-contrast-rgb: 255, 255, 255;
   --ion-color-danger-shade: #e04055;
   --ion-color-danger-tint: #ff5b71;
 
   --ion-color-dark: #f4f5f8;
-  --ion-color-dark-rgb: 244,245,248;
+  --ion-color-dark-rgb: 244, 245, 248;
   --ion-color-dark-contrast: #000000;
-  --ion-color-dark-contrast-rgb: 0,0,0;
+  --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-rgb: 152, 154, 162;
   --ion-color-medium-contrast: #000000;
-  --ion-color-medium-contrast-rgb: 0,0,0;
+  --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-rgb: 34, 36, 40;
   --ion-color-light-contrast: #ffffff;
-  --ion-color-light-contrast-rgb: 255,255,255;
+  --ion-color-light-contrast-rgb: 255, 255, 255;
   --ion-color-light-shade: #1e2023;
   --ion-color-light-tint: #383a3e;
 }
 
+/*
+ * iOS Dark Theme
+ * -------------------------------------------
+ */
+
 .ios body {
   --ion-background-color: #000000;
-  --ion-background-color-rgb: 0,0,0;
+  --ion-background-color-rgb: 0, 0, 0;
 
   --ion-text-color: #ffffff;
-  --ion-text-color-rgb: 255,255,255;
+  --ion-text-color-rgb: 255, 255, 255;
 
   --ion-color-step-50: #0d0d0d;
   --ion-color-step-100: #1a1a1a;
@@ -90,18 +100,28 @@
   --ion-color-step-900: #e6e6e6;
   --ion-color-step-950: #f2f2f2;
 
-  --ion-item-background: #1c1c1c;
+  --ion-item-background: #000000;
 
-  --ion-toolbar-background: #000;
-  --ion-toolbar-color: #fff;
+  --ion-card-background: #1c1c1d;
 }
 
+.ios ion-modal {
+  --ion-background-color: var(--ion-color-step-100);
+  --ion-toolbar-background: var(--ion-color-step-150);
+  --ion-toolbar-border-color: var(--ion-color-step-250);
+}
+
+/*
+ * Material Design Dark Theme
+ * -------------------------------------------
+ */
+
 .md body {
   --ion-background-color: #121212;
-  --ion-background-color-rgb: 18,18,18;
+  --ion-background-color-rgb: 18, 18, 18;
 
   --ion-text-color: #ffffff;
-  --ion-text-color-rgb: 255,255,255;
+  --ion-text-color-rgb: 255, 255, 255;
 
   --ion-border-color: #222222;
 
@@ -125,12 +145,11 @@
   --ion-color-step-900: #e7e7e7;
   --ion-color-step-950: #f3f3f3;
 
-  --ion-item-background: #1a1b1e;
-}
+  --ion-item-background: #1e1e1e;
 
-ion-modal.ios {
-  --ion-background-color: var(--ion-color-step-100);
-  --ion-toolbar-background: var(--ion-color-step-150);
-  --ion-toolbar-border-color: var(--ion-color-step-250);
-  --ion-item-background: var(--ion-color-step-150);
+  --ion-toolbar-background: #1f1f1f;
+
+  --ion-tab-bar-background: #1f1f1f;
+
+  --ion-card-background: #1e1e1e;
 }