func (p ToolbarPainter) PaintButtonItem(canvas widget.Canvas, state toolbar.PaintButtonState) {
	if state.Bounds.IsEmpty() {
		return
	}
	colors := p.resolveColors()

	// Background on hover/press (disabled items get no feedback).
	if !state.Disabled {
		bg := widget.ColorTransparent
		if state.Pressed {
			bg = colors.PressedBg
		} else if state.Hovered {
			bg = colors.HoverBg
		}
		if !bg.IsTransparent() {
			canvas.DrawRoundRect(state.Bounds, bg, m3ToolbarItemRadius)
		}
	}

	// Icon color.
	fg := colors.IconColor
	if state.Disabled {
		fg = colors.DisabledFg
	}

	// Draw icon centered in the button area.
	iconBounds := m3ToolbarIconBounds(state.Bounds, state.ShowLabel)
	icon.Draw(canvas, state.Icon, iconBounds, fg)

	// Draw label text if ShowLabel is true.
	if state.ShowLabel && state.Label != "" {
		textBounds := m3ToolbarTextBounds(state.Bounds, iconBounds)
		canvas.DrawText(state.Label, textBounds, m3ToolbarFontSize, fg, false, widget.TextAlignLeft)
	}

	// Focus ring.
	if state.Focused && !state.Disabled {
		ringBounds := state.Bounds.Expand(m3ToolbarFocusRingOffset)
		canvas.StrokeRoundRect(ringBounds, colors.FocusRing, m3ToolbarItemRadius+m3ToolbarFocusRingOffset, m3ToolbarFocusRingWidth)
	}
}

func (p ToolbarPainter) PaintSeparator(canvas widget.Canvas, bounds geometry.Rect) {
	if bounds.IsEmpty() {
		return
	}
	colors := p.resolveColors()
	centerX := bounds.Min.X + bounds.Width()/2
	canvas.DrawLine(
		geometry.Pt(centerX, bounds.Min.Y+m3ToolbarSepInset),
		geometry.Pt(centerX, bounds.Max.Y-m3ToolbarSepInset),
		colors.SeparatorFg, m3ToolbarSepWidth,
	)
}

func (p ToolbarPainter) PaintToolbar(canvas widget.Canvas, state toolbar.PaintToolbarState) {
	if state.Bounds.IsEmpty() {
		return
	}
	colors := p.resolveColors()
	canvas.DrawRect(state.Bounds, colors.Background)
}

type ToolbarPainter struct {
	Theme *Theme	// nil uses default M3 purple fallback
}