func (p TitleBarPainter) DrawBackground(canvas widget.Canvas, bounds geometry.Rect, _ titlebar.BackgroundState) {
	if bounds.IsEmpty() {
		return
	}
	colors := p.resolveColors()

	// Dark header background.
	canvas.DrawRect(bounds, colors.Background)

	// 1px bottom border.
	borderRect := geometry.NewRect(
		bounds.Min.X,
		bounds.Max.Y-dtTitleBarBorderWidth,
		bounds.Width(),
		dtTitleBarBorderWidth,
	)
	canvas.DrawRect(borderRect, colors.BorderColor)
}

func (p TitleBarPainter) DrawControlButton(canvas widget.Canvas, bounds geometry.Rect, control titlebar.ControlType, state titlebar.ControlState) {
	if bounds.IsEmpty() {
		return
	}
	colors := p.resolveColors()

	// Background on hover/press.
	isClose := control == titlebar.ControlClose
	bg := dtControlBackground(isClose, state, colors)
	if !bg.IsTransparent() {
		canvas.DrawRect(bounds, bg)
	}

	// Icon color.
	fg := colors.IconColor
	if isClose && state.Hovered {
		fg = colors.CloseHoverIconFg
	}

	// Draw icon glyph centered.
	cx := bounds.Min.X + bounds.Width()/2
	cy := bounds.Min.Y + bounds.Height()/2

	switch control {
	case titlebar.ControlMinimize:
		drawMinimizeIcon(canvas, cx, cy, fg)
	case titlebar.ControlMaximize:
		drawMaximizeIcon(canvas, cx, cy, fg)
	case titlebar.ControlRestore:
		drawRestoreIcon(canvas, cx, cy, fg, colors.Background)
	case titlebar.ControlClose:
		drawCloseIcon(canvas, cx, cy, fg)
	}
}

type TitleBarPainter struct {
	Theme *Theme	// nil uses default DevTools dark fallback
}