look_and_feel = javax.swing.plaf.nimbus.NimbusLookAndFeel
#look_and_feel = javax.swing.plaf.metal.MetalLookAndFeel
#look_and_feel = com.sun.java.swing.plaf.motif.MotifLookAndFeel
#look_and_feel = com.sun.java.swing.plaf.gtk.GTKLookAndFeel
#look_and_feel = com.sun.java.swing.plaf.windows.WindowsLookAndFeel