diff --git a/tracker/gioui/instrument_editor.go b/tracker/gioui/instrument_editor.go
index 772e5ea..a491e0a 100644
--- a/tracker/gioui/instrument_editor.go
+++ b/tracker/gioui/instrument_editor.go
@@ -146,7 +146,7 @@ func (ul *InstrumentEditor) layoutList(gtx C) D {
 			}),
 		)
 	}
-	return Surface{Gray: 30, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, surface)
+	return Surface{Height: 4, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, surface)
 }
 
 func (ul *InstrumentEditor) update(gtx C) {
@@ -279,7 +279,7 @@ func (pe *InstrumentEditor) layoutTable(gtx C) D {
 	if pe.searching.Value() {
 		editorFunc = pe.layoutUnitTypeChooser
 	}
-	return Surface{Gray: 24, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
+	return Surface{Height: 3, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
 		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
 			layout.Flexed(1, editorFunc),
 			layout.Rigid(pe.layoutFooter),
diff --git a/tracker/gioui/instrument_presets.go b/tracker/gioui/instrument_presets.go
index 47d873f..e517bb5 100644
--- a/tracker/gioui/instrument_presets.go
+++ b/tracker/gioui/instrument_presets.go
@@ -104,7 +104,7 @@ func (ip *InstrumentPresets) layout(gtx C) D {
 		return dims
 	}
 	dirSurface := func(gtx C) D {
-		return Surface{Gray: 36, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, dirs)
+		return Surface{Height: 5, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, dirs)
 	}
 	resultElem := func(gtx C, i int) D {
 		gtx.Constraints.Min.X = gtx.Constraints.Max.X
@@ -142,7 +142,7 @@ func (ip *InstrumentPresets) layout(gtx C) D {
 		return dims
 	}
 	resultSurface := func(gtx C) D {
-		return Surface{Gray: 30, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, results)
+		return Surface{Height: 4, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, results)
 	}
 	bottom := func(gtx C) D {
 		return layout.Flex{Axis: layout.Horizontal}.Layout(gtx,
@@ -169,7 +169,7 @@ func (ip *InstrumentPresets) layout(gtx C) D {
 		)
 		return D{Size: m}
 	}
-	return Surface{Gray: 24, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, f)
+	return Surface{Height: 3, Focus: tr.PatchPanel.TreeFocused(gtx)}.Layout(gtx, f)
 }
 
 func (ip *InstrumentPresets) layoutSearch(gtx C) D {
diff --git a/tracker/gioui/note_editor.go b/tracker/gioui/note_editor.go
index 07f5c0d..aef442f 100644
--- a/tracker/gioui/note_editor.go
+++ b/tracker/gioui/note_editor.go
@@ -149,7 +149,7 @@ func (te *NoteEditor) Layout(gtx layout.Context) layout.Dimensions {
 
 	defer clip.Rect(image.Rect(0, 0, gtx.Constraints.Max.X, gtx.Constraints.Max.Y)).Push(gtx.Ops).Pop()
 
-	return Surface{Gray: 24, Focus: te.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
+	return Surface{Height: 3, Focus: te.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
 		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
 			layout.Rigid(func(gtx C) D {
 				return te.layoutButtons(gtx, t)
@@ -162,7 +162,7 @@ func (te *NoteEditor) Layout(gtx layout.Context) layout.Dimensions {
 }
 
 func (te *NoteEditor) layoutButtons(gtx C, t *Tracker) D {
-	return Surface{Gray: 37, Focus: te.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
+	return Surface{Height: 4, Focus: te.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
 		addSemitoneBtn := ActionBtn(t.AddSemitone(), t.Theme, te.AddSemitoneBtn, "+1", "Add semitone")
 		subtractSemitoneBtn := ActionBtn(t.SubtractSemitone(), t.Theme, te.SubtractSemitoneBtn, "-1", "Subtract semitone")
 		addOctaveBtn := ActionBtn(t.AddOctave(), t.Theme, te.AddOctaveBtn, "+12", "Add octave")
diff --git a/tracker/gioui/order_editor.go b/tracker/gioui/order_editor.go
index e4731ec..52b8b01 100644
--- a/tracker/gioui/order_editor.go
+++ b/tracker/gioui/order_editor.go
@@ -120,7 +120,7 @@ func (oe *OrderEditor) Layout(gtx C) D {
 	table := FilledScrollTable(t.Theme, oe.scrollTable)
 	table.ColumnTitleHeight = orderTitleHeight
 
-	return Surface{Gray: 24, Focus: oe.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
+	return Surface{Height: 3, Focus: oe.scrollTable.TreeFocused(gtx)}.Layout(gtx, func(gtx C) D {
 		return table.Layout(gtx, cell, colTitle, rowTitle, nil, rowTitleBg)
 	})
 }
diff --git a/tracker/gioui/patch_panel.go b/tracker/gioui/patch_panel.go
index 0975c77..81c71ba 100644
--- a/tracker/gioui/patch_panel.go
+++ b/tracker/gioui/patch_panel.go
@@ -174,7 +174,7 @@ func (it *InstrumentTools) Layout(gtx C) D {
 			layout.Rigid(addInstrumentBtn.Layout),
 		)
 	}
-	return Surface{Gray: 37, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, btns)
+	return Surface{Height: 4, Focus: t.PatchPanel.TreeFocused(gtx)}.Layout(gtx, btns)
 }
 
 func (it *InstrumentTools) update(gtx C, tr *Tracker) {
diff --git a/tracker/gioui/song_panel.go b/tracker/gioui/song_panel.go
index f0bbf7d..04a1383 100644
--- a/tracker/gioui/song_panel.go
+++ b/tracker/gioui/song_panel.go
@@ -467,7 +467,7 @@ func (pb *PlayBar) Layout(gtx C) D {
 	followBtn := ToggleIconBtn(tr.Follow(), tr.Theme, pb.FollowBtn, icons.ActionSpeakerNotesOff, icons.ActionSpeakerNotes, pb.followOffHint, pb.followOnHint)
 	loopBtn := ToggleIconBtn(tr.LoopToggle(), tr.Theme, pb.LoopBtn, icons.NavigationArrowForward, icons.AVLoop, pb.loopOffHint, pb.loopOnHint)
 
-	return Surface{Gray: 37}.Layout(gtx, func(gtx C) D {
+	return Surface{Height: 4}.Layout(gtx, func(gtx C) D {
 		return layout.Flex{Axis: layout.Horizontal, Alignment: layout.Middle}.Layout(gtx,
 			layout.Flexed(1, playBtn.Layout),
 			layout.Rigid(rewindBtn.Layout),
diff --git a/tracker/gioui/surface.go b/tracker/gioui/surface.go
index ae52cfd..9bdd603 100644
--- a/tracker/gioui/surface.go
+++ b/tracker/gioui/surface.go
@@ -9,25 +9,26 @@ import (
 )
 
 type Surface struct {
-	Gray  int
-	Inset layout.Inset
-	Focus bool
+	Height int
+	Inset  layout.Inset
+	Focus  bool
 }
 
 func (s Surface) Layout(gtx C, widget layout.Widget) D {
-	return layout.Background{}.Layout(gtx,
-		func(gtx C) D {
-			gray := s.Gray
-			if s.Focus {
-				gray += 8
-			}
-			gray8 := uint8(min(max(gray, 0), 255))
-			color := color.NRGBA{R: gray8, G: gray8, B: gray8, A: 255}
-			paint.FillShape(gtx.Ops, color, clip.Rect{Max: gtx.Constraints.Min}.Op())
-			return D{Size: gtx.Constraints.Min}
-		},
-		func(gtx C) D {
-			return s.Inset.Layout(gtx, widget)
-		},
-	)
+	t := TrackerFromContext(gtx)
+	t.surfaceHeight += s.Height
+	bg := func(gtx C) D {
+		gray := s.Height * 8
+		if s.Focus {
+			gray += 8
+		}
+		gray8 := uint8(min(max(gray, 0), 255))
+		color := color.NRGBA{R: gray8, G: gray8, B: gray8, A: 255}
+		paint.FillShape(gtx.Ops, color, clip.Rect{Max: gtx.Constraints.Min}.Op())
+		return D{Size: gtx.Constraints.Min}
+	}
+	fg := func(gtx C) D { return s.Inset.Layout(gtx, widget) }
+	dims := layout.Background{}.Layout(gtx, bg, fg)
+	t.surfaceHeight -= s.Height
+	return dims
 }
diff --git a/tracker/gioui/tracker.go b/tracker/gioui/tracker.go
index 2c9361c..c96ea86 100644
--- a/tracker/gioui/tracker.go
+++ b/tracker/gioui/tracker.go
@@ -56,6 +56,8 @@ type (
 		preferences Preferences
 
 		*tracker.Model
+
+		surfaceHeight int
 	}
 
 	ShowManual Tracker