diff --git a/tests/test_style_importance.py b/tests/test_style_importance.py
new file mode 100644
index 000000000..fc5547416
--- /dev/null
+++ b/tests/test_style_importance.py
@@ -0,0 +1,102 @@
+from textual.app import App, ComposeResult
+from textual.color import Color
+from textual.containers import Container
+from textual.css.scalar import Scalar, ScalarOffset
+
+
+class StyleApp(App[None]):
+    CSS = """
+    Container {
+        border: round green !important;
+        outline: round green !important;
+        align: right bottom !important;
+        content-align: right bottom !important;
+        offset: 17 23 !important;
+        overflow: hidden hidden !important;
+        padding: 10 20 30 40 !important;
+        scrollbar-size: 23 42 !important;
+    }
+
+    Container.more-specific {
+        border: solid red;
+        outline: solid red;
+        align: center middle;
+        content-align: center middle;
+        offset: 0 0;
+        overflow: scroll scroll;
+        padding: 1 2 3 4;
+        scrollbar-size: 1 2;
+    }
+    """
+
+    def compose(self) -> ComposeResult:
+        yield Container(classes="more-specific")
+
+
+async def test_border_importance():
+    """Border without sides should support !important"""
+    async with StyleApp().run_test() as pilot:
+        border = pilot.app.query_one(Container).styles.border
+        desired = ("round", Color.parse("green"))
+        assert border.top == desired
+        assert border.left == desired
+        assert border.bottom == desired
+        assert border.right == desired
+
+
+async def test_outline_importance():
+    """Outline without sides should support !important"""
+    async with StyleApp().run_test() as pilot:
+        outline = pilot.app.query_one(Container).styles.outline
+        desired = ("round", Color.parse("green"))
+        assert outline.top == desired
+        assert outline.left == desired
+        assert outline.bottom == desired
+        assert outline.right == desired
+
+
+async def test_align_importance():
+    """Align without direction should support !important"""
+    async with StyleApp().run_test() as pilot:
+        assert pilot.app.query_one(Container).styles.align == ("right", "bottom")
+
+
+async def test_content_align_importance():
+    """Content align without direction should support !important"""
+    async with StyleApp().run_test() as pilot:
+        assert pilot.app.query_one(Container).styles.content_align == (
+            "right",
+            "bottom",
+        )
+
+
+async def test_offset_importance():
+    """Offset without direction should support !important"""
+    async with StyleApp().run_test() as pilot:
+        assert pilot.app.query_one(Container).styles.offset == ScalarOffset.from_offset(
+            (17, 23)
+        )
+
+
+async def test_overflow_importance():
+    """Overflow without direction should support !important"""
+    async with StyleApp().run_test() as pilot:
+        assert pilot.app.query_one(Container).styles.overflow_x == "hidden"
+        assert pilot.app.query_one(Container).styles.overflow_y == "hidden"
+
+
+async def test_padding_importance():
+    """Padding without sides should support !important"""
+    async with StyleApp().run_test() as pilot:
+        padding = pilot.app.query_one(Container).styles.padding
+        assert padding.top == 10
+        assert padding.left == 40
+        assert padding.bottom == 30
+        assert padding.right == 20
+
+
+async def test_scrollbar_size_importance():
+    """Scrollbar size without direction should support !important"""
+    async with StyleApp().run_test() as pilot:
+        assert pilot.app.query_one(Container).styles.scrollbar_size_horizontal == 23
+        assert pilot.app.query_one(Container).styles.scrollbar_size_vertical == 42