snapshot test

src/textual/color.py

@@ -378,7 +378,7 @@ def blend(
         Returns:
             A new color.
         """
-        if self.ansi is not None:
+        if destination.ansi is not None:
             return destination
         if factor <= 0:
             return self

src/textual/command.py

@@ -459,6 +459,10 @@ class CommandPalette(SystemModalScreen):
         #--container {
             display: none;
         }
+
+        &:ansi {
+            background: transparent;
+        }
     }
 
     CommandPalette.-ready {

src/textual/renderables/background_screen.py

@@ -50,6 +50,20 @@ def process_segments(
 
         NULL_STYLE = Style()
 
+        if color.a == 0:
+            # Special case for transparent color
+            for segment in segments:
+                text, style, control = segment
+                if control:
+                    yield segment
+                else:
+                    yield _Segment(
+                        text,
+                        NULL_STYLE if style is None else style.clear_meta_and_links(),
+                        control,
+                    )
+            return
+
         for segment in segments:
             text, style, control = segment
             if control:

src/textual/screen.py

@@ -1449,6 +1449,9 @@ class ModalScreen(Screen[ScreenResultType]):
         layout: vertical;
         overflow-y: auto;
         background: $background 60%;
+        &:ansi {
+            background: transparent;
+        }
     }
     """
 

src/textual/widget.py

@@ -293,6 +293,7 @@ class Widget(DOMNode):
         link-background-hover: $accent;
         link-color-hover: $text;
         link-style-hover: bold not underline;
+        background: transparent;
     }
     """
     COMPONENT_CLASSES: ClassVar[set[str]] = set()

tests/snapshot_tests/test_snapshots.py

@@ -1921,3 +1921,23 @@ def compose(self) -> ComposeResult:
 
     app = ANSIApp(ansi_color=True)
     assert snap_compare(app)
+
+
+def test_ansi_command_palette(snap_compare):
+    """Test command palette on top of ANSI colors."""
+
+    class CommandPaletteApp(App[None]):
+        CSS = """
+        Label {
+            width: 1fr;
+        }
+        """
+
+        def compose(self) -> ComposeResult:
+            yield Label("[red]Red[/] [magenta]Magenta[/] " * 200)
+
+        def on_mount(self) -> None:
+            self.action_command_palette()
+
+    app = CommandPaletteApp(ansi_color=True)
+    assert snap_compare(app)