function leistung() {
	
	t_border1 	=	document.getElementById('border1');
	t_border2	 	=	document.getElementById('border2');
	t_border3	 	=	document.getElementById('border3');
	t_leistung1	= 	document.getElementById('leistung1');
	t_leistung2	= 	document.getElementById('leistung2');
	t_leistung3	= 	document.getElementById('leistung3');
	
	if ("none" == t_border1.style.display) t_border1.style.display = "block";	else t_border1.style.display = "none";
	if ("none" == t_border2.style.display) t_border2.style.display = "block";	else t_border2.style.display = "none";
	if ("none" == t_border3.style.display) t_border3.style.display = "block";	else t_border3.style.display = "none";
	
	if ("none" == t_leistung1.style.display) t_leistung1.style.display = "block"; else t_leistung1.style.display = "none";
	if ("none" == t_leistung2.style.display) t_leistung2.style.display = "block"; else t_leistung2.style.display = "none";
	if ("none" == t_leistung3.style.display) t_leistung3.style.display = "block"; else t_leistung3.style.display = "none";
	
}