diff --git a/src/textual/widgets/_selection_list.py b/src/textual/widgets/_selection_list.py
index a448c5e412..f8dece7142 100644
--- a/src/textual/widgets/_selection_list.py
+++ b/src/textual/widgets/_selection_list.py
@@ -97,15 +97,15 @@ class SelectionList(Generic[SelectionType], OptionList):
         height: auto;
     }
 
-    .-light-mode SelectionList:focus > .selection-list--button-selected {
+    SelectionList:light:focus > .selection-list--button-selected {
         color: $primary;
     }
 
-    .-light-mode SelectionList > .selection-list--button-selected-highlighted {
+    SelectionList:light > .selection-list--button-selected-highlighted {
         color: $primary;
     }
 
-    .-light-mode SelectionList:focus > .selection-list--button-selected-highlighted {
+    SelectionList:light:focus > .selection-list--button-selected-highlighted {
         color: $primary;
     }
 
diff --git a/src/textual/widgets/_toggle_button.py b/src/textual/widgets/_toggle_button.py
index 4c29c236ae..90828c7ac1 100644
--- a/src/textual/widgets/_toggle_button.py
+++ b/src/textual/widgets/_toggle_button.py
@@ -94,16 +94,16 @@ class ToggleButton(Static, can_focus=True):
 
     /* Light mode overrides. */
 
-    App.-light-mode ToggleButton > .toggle--button {
+    ToggleButton:light > .toggle--button {
         color: $background;
         background: $foreground 10%;
     }
 
-    App.-light-mode ToggleButton:focus > .toggle--button {
+    ToggleButton:light:focus > .toggle--button {
         background: $foreground 25%;
     }
 
-    App.-light-mode ToggleButton.-on > .toggle--button {
+    ToggleButton:light.-on > .toggle--button {
         color: $primary;
     }
     """  # TODO: https://github.com/Textualize/textual/issues/1780