fix(multiple): improve dark theme visibility in menu, overlay, and portal examples (#33367)

BHUVANSH855 · crisbeto · commit 2995797ded37 · 2026-06-12T15:00:44.000+02:00
(cherry picked from commit eb2c033)
diff --git a/src/components-examples/cdk/menu/cdk-menu-nested-context/cdk-menu-nested-context-example.css b/src/components-examples/cdk/menu/cdk-menu-nested-context/cdk-menu-nested-context-example.css
@@ -1,6 +1,6 @@
 .example-context-area {
   display: inline-grid;
-  border: 2px dashed black;
+  border: 2px dashed white;
 }
 
 .example-context-area .example-context-area {
diff --git a/src/components-examples/cdk/menu/cdk-menu-standalone-menu/cdk-menu-standalone-menu-example.css b/src/components-examples/cdk/menu/cdk-menu-standalone-menu/cdk-menu-standalone-menu-example.css
@@ -24,6 +24,18 @@
   flex: 1;
 }
 
+.example-standalone-trigger {
+  background-color: rgb(239, 239, 239);
+}
+
+.example-standalone-trigger:hover {
+  background-color: rgb(208, 208, 208);
+}
+
+.example-standalone-trigger:active {
+  background-color: rgb(170, 170, 170);
+}
+
 .example-menu-item:hover {
   background-color: rgb(208, 208, 208);
 }
diff --git a/src/components-examples/cdk/overlay/cdk-overlay-basic/cdk-overlay-basic-example.css b/src/components-examples/cdk/overlay/cdk-overlay-basic/cdk-overlay-basic-example.css
@@ -3,6 +3,7 @@
   border: solid 1px #ccc;
   border-radius: 5px;
   background: #fff;
+  color: CanvasText;
   text-align: center;
   padding: 10px;
   margin: 0;
diff --git a/src/components-examples/cdk/portal/cdk-portal-overview/cdk-portal-overview-example.css b/src/components-examples/cdk/portal/cdk-portal-overview/cdk-portal-overview-example.css
@@ -1,7 +1,7 @@
 .example-portal-outlet {
   margin-bottom: 10px;
   padding: 10px;
-  border: 1px dashed black;
+  border: 1px dashed white;
   width: 250px;
   height: 250px;
 }

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,6 @@`
`1`	`1`	`.example-context-area {`
`2`	`2`	`display: inline-grid;`
`3`		`- border: 2px dashed black;`
	`3`	`+ border: 2px dashed white;`
`4`	`4`	`}`
`5`	`5`
`6`	`6`	`.example-context-area .example-context-area {`
Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`	`.example-portal-outlet {`
`2`	`2`	`margin-bottom: 10px;`
`3`	`3`	`padding: 10px;`
`4`		`- border: 1px dashed black;`
	`4`	`+ border: 1px dashed white;`
`5`	`5`	`width: 250px;`
`6`	`6`	`height: 250px;`
`7`	`7`	`}`