mezontleTeam/Main.java

import javax.swing.*;
import java.awt.*;

public class Main {
    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            JFrame frame = new JFrame("Login");
            frame.setContentPane(new ventana1().panel);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            Dimension pantalla = Toolkit.getDefaultToolkit().getScreenSize();
            int height = pantalla.height;
            int width = pantalla.width;
            frame.setSize(width/2, height/2);
            frame.setLocationRelativeTo(null);
            frame.pack();
            frame.setVisible(true);
        });
    }
}