$('#portfolio').mouseover(function() {
	$(this).attr('src', 'http://polinfor.pl/Public/Layouts/Polinfor/portfolio_green.jpg');
}
);
$('#portfolio').mouseout(function() {
	$(this).attr('src', 'Public/Layouts/Polinfor/portfolio_blue.jpg');
}
);

$('#nasi_klienci').mouseover(function() {
	$(this).attr('src', 'http://polinfor.pl/Public/Layouts/Polinfor/nasi_klienci_green.jpg');
}
);
$('#nasi_klienci').mouseout(function() {
	$(this).attr('src', 'Public/Layouts/Polinfor/nasi_klienci_blue.jpg');
}
);

$('#kontakt').mouseover(function() {
	$(this).attr('src', 'http://polinfor.pl/Public/Layouts/Polinfor/kontakt_green.jpg');
}
);
$('#kontakt').mouseout(function() {
	$(this).attr('src', 'Public/Layouts/Polinfor/kontakt_blue.jpg');
}
);