private UIElement _BuildLogBlock(FlowDocument log)
        {
            log.FontFamily = new FontFamily("SimSun");
            log.FontSize = 15;
            double width = log.GetFormattedText().WidthIncludingTrailingWhitespace + 20;
            RichTextBox rtb = new RichTextBox()
            {
                Document = log,
                Foreground = new SolidColorBrush(Color.FromArgb(0xFF, 0xFF, 0xEE, 0x99)),
                Background = new SolidColorBrush(Colors.Transparent),
                BorderThickness = new Thickness(0d),
                Width = width,
                Effect = new DropShadowEffect() { Color = Colors.Black, BlurRadius = 3, ShadowDepth = 0 },
            };

            Border border = new Border()
            {
                CornerRadius = new CornerRadius(3d),
                Child = rtb,
                Width = width,
                Background = new SolidColorBrush(Color.FromArgb(0xFF, 0x3D, 0x3A, 0x2C)),
                BorderThickness = new Thickness(1d),
                Opacity = 0d,
                HorizontalAlignment = System.Windows.HorizontalAlignment.Center
            };

            return border;
        }