Style Scrollbar separately in Aluminum

internal/styles/aluminum/aluminum.tss

@@ -143,6 +143,33 @@ $BorderOuterShadow    = #a4afc0                         / 0 1 1 0;
 	MinimumSize: 12;
 }
 
+*.Scrollbar {
+	Border: $BorderEngraved, $BorderGap, $BorderInnerShadow;
+	Color:  $ColorGutter;
+}
+
+*.Scrollbar[focused] {
+	Border: $BorderEngraved, $BorderFocused, $BorderInnerShadow;
+}
+
+*.Scrollbar[hovered] {
+	Color: $ColorGutterHovered;
+}
+
+*.Scrollbar[horizontal] {
+	MinimumSize: 48 0;
+}
+
+*.Scrollbar[vertical] {
+	MinimumSize: 0 48;
+}
+
+*.ScrollbarHandle {
+	Border:      $BorderOuterShadow, $BorderGap, $BorderLifted;
+	Color:       $ColorRaised;
+	MinimumSize: 12;
+}
+
 *.ScrollContainer {
 	Gap: 0;
 }