protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g.create();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
Color dark = new Color(1.0F, 1.0F, 1.0F, 0.0F);
Color light = new Color(1.0F, 1.0F, 1.0F, 0.18F);
GradientPaint paint = new GradientPaint(0.0F, 0.0F, light, 0.0F, getHeight(), dark);
g2.setPaint(paint);
g2.fillRoundRect(0, 0, getWidth() - 2, getHeight() - 2, 20, 20);
g2.setStroke(new BasicStroke(1.4F));
g2.setColor(Color.WHITE.brighter());
g2.drawRoundRect(0, 0, getWidth() - 2, getHeight() - 2, 20, 20);
g2.dispose();
}
