it's -> its

docs/guide/events.md

@@ -157,7 +157,7 @@ Textual uses the following scheme to map messages classes on to a Python method.
 
 Messages have a namespace if they are defined as a child class of a Widget.
 The namespace is the name of the parent class.
-For instance, the builtin `Input` class defines it's `Changed` message as follow:
+For instance, the builtin `Input` class defines its `Changed` message as follows:
 
 ```python
 class Input(Widget):

docs/widgets/text_area.md

@@ -177,7 +177,7 @@ the cursor, selection, gutter, and more.
 
 #### Default theme
 
-The default `TextArea` theme is called `css`, which takes it's values entirely from CSS.
+The default `TextArea` theme is called `css`, which takes its values entirely from CSS.
 This means that the default appearance of the widget fits nicely into a standard Textual application,
 and looks right on both dark and light mode.
 

src/textual/_compositor.py

@@ -582,7 +582,7 @@ def add_widget(
 
             Args:
                 widget: The widget to add.
-                virtual_region: The Widget region relative to it's container.
+                virtual_region: The Widget region relative to its container.
                 region: The region the widget will occupy.
                 order: Painting order information.
                 layer_order: The order of the widget in its layer.

src/textual/_layout.py

@@ -20,7 +20,7 @@
 @dataclass
 class DockArrangeResult:
     placements: list[WidgetPlacement]
-    """A `WidgetPlacement` for every widget to describe it's location on screen."""
+    """A `WidgetPlacement` for every widget to describe its location on screen."""
     widgets: set[Widget]
     """A set of widgets in the arrangement."""
     scroll_spacing: Spacing

src/textual/css/_style_properties.py

@@ -290,7 +290,7 @@ def __get__(
 
         Returns:
             A ``tuple[EdgeType, Style]`` containing the string type of the box and
-                it's style. Example types are "rounded", "solid", and "dashed".
+                its style. Example types are "rounded", "solid", and "dashed".
         """
         return obj.get_rule(self.name) or ("", self._default_color)  # type: ignore[return-value]
 

src/textual/widget.py

@@ -1813,7 +1813,7 @@ def container_viewport(self) -> Region:
 
     @property
     def virtual_region(self) -> Region:
-        """The widget region relative to it's container (which may not be visible,
+        """The widget region relative to its container (which may not be visible,
         depending on scroll offset).
 
 
@@ -2845,7 +2845,7 @@ def scroll_to_widget(
                     scrolled = True
 
             # Adjust the region by the amount we just scrolled it, and convert to
-            # it's parent's virtual coordinate system.
+            # its parent's virtual coordinate system.
 
             region = (
                 (