Applying styles to button

sandbox/buttons.css

@@ -0,0 +1,8 @@
+#foo {
+    text-style: underline;
+    background: rebeccapurple;
+}
+
+#foo:hover {
+    background: greenyellow;
+}

sandbox/buttons.py

@@ -18,7 +18,7 @@ class ButtonsApp(App[str]):
         self.exit(event.button.id)
 
 
-app = ButtonsApp(log_path="textual.log", log_verbosity=2)
+app = ButtonsApp(log_path="textual.log", css_path="buttons.css", log_verbosity=2)
 
 if __name__ == "__main__":
     result = app.run()

src/textual/widget.py

@@ -464,7 +464,6 @@ class Widget(DOMNode):
         Returns:
             RenderableType: A new renderable.
         """
-
         renderable = self.render(self.styles.rich_style)
 
         styles = self.styles
@@ -478,13 +477,13 @@ class Widget(DOMNode):
             horizontal, vertical = content_align
             renderable = Align(renderable, horizontal, vertical=vertical)
 
+        renderable = Padding(renderable, styles.padding)
+
         renderable_text_style = parent_text_style + text_style
         if renderable_text_style:
             style = Style.from_color(text_style.color, text_style.bgcolor)
             renderable = Styled(renderable, style)
 
-        renderable = Padding(renderable, styles.padding)
-
         if styles.border:
             renderable = Border(
                 renderable,

src/textual/widgets/_button.py

@@ -4,7 +4,7 @@ from typing import cast
 
 from rich.console import RenderableType
 from rich.style import Style
-from rich.text import Text
+from rich.text import Text, TextType
 
 from .. import events
 from ..message import Message
@@ -49,7 +49,7 @@ class Button(Widget, can_focus=True):
 
     def __init__(
         self,
-        label: RenderableType | None = None,
+        label: TextType | None = None,
         disabled: bool = False,
         *,
         name: str | None = None,
@@ -58,7 +58,11 @@ class Button(Widget, can_focus=True):
     ):
         super().__init__(name=name, id=id, classes=classes)
 
-        self.label = self.css_identifier_styled if label is None else label
+        if label is None:
+            label = self.css_identifier_styled
+
+        self.label: Text = self.validate_label(label)
+
         self.disabled = disabled
         if disabled:
             self.add_class("-disabled")
@@ -72,7 +76,7 @@ class Button(Widget, can_focus=True):
         return label
 
     def render(self, style: Style) -> RenderableType:
-        return self.label
+        return Text.styled(self.label.plain, style)
 
     async def on_click(self, event: events.Click) -> None:
         event.stop()