feat(theming): add --color-mark CSS variable for highlighted text

Required for nextcloud/text#8309

Signed-off-by: Jonas <jonas@freesources.org>

Author: mejo-

apps/theming/css/default.css

@@ -42,6 +42,7 @@
   --color-info-hover: #b5e6f6;
   --color-info-text: #0066AC;
   --color-favorite: #A37200;
+  --color-mark: #fff0c7;
   /** @deprecated use css color functions */
   --color-error-rgb: 255,231,231;
   /** @deprecated use css color functions */

apps/theming/lib/Themes/DarkTheme.php

@@ -115,6 +115,7 @@ public function getCSSVariables(): array {
 				'--color-info-hover' => $this->util->lighten($colorInfo, 10),
 				'--color-info-text' => $colorInfoText,
 				'--color-favorite' => '#ffde00',
+				'--color-mark' => '#4d3800',
 				// deprecated
 				'--color-error-rgb' => join(',', $this->util->hexToRGB($colorError)),
 				'--color-warning-rgb' => join(',', $this->util->hexToRGB($colorWarning)),

apps/theming/lib/Themes/DefaultTheme.php

@@ -165,6 +165,7 @@ public function getCSSVariables(): array {
 			'--color-info-hover' => $this->util->darken($colorInfo, 7),
 			'--color-info-text' => $colorInfoText,
 			'--color-favorite' => '#A37200',
+			'--color-mark' => '#fff0c7',
 			// deprecated
 			'--color-error-rgb' => join(',', $this->util->hexToRGB($colorError)),
 			'--color-warning-rgb' => join(',', $this->util->hexToRGB($colorWarning)),

core/css/server.css

@@ -85,6 +85,10 @@ select, .button span, label {
 	cursor: pointer;
 }
 
+mark {
+	background-color: var(--color-mark);
+}
+
 ul {
 	list-style: none;
 }