public override void Draw(State state, Rect rect)
        {
            base.Draw(state, rect);

            // Draw the panels.
            PanelAvailable.Draw(PrepareCarefully.Instance.State);
            PanelSelected.Draw(PrepareCarefully.Instance.State);
        }
        protected override void Resize(Rect rect)
        {
            base.Resize(rect);

            Vector2 panelMargin = Style.SizePanelMargin;

            float availableWidth  = rect.width - panelMargin.x;
            float availableHeight = rect.height;
            float panelWidth      = Mathf.Floor(availableWidth / 2);

            PanelAvailable.Resize(new Rect(rect.x, rect.y, panelWidth, availableHeight));
            PanelSelected.Resize(new Rect(PanelAvailable.PanelRect.xMax + panelMargin.x, rect.y,
                                          panelWidth, availableHeight));
        }