/******* common & immer ***********/

window.name = 'page';

/******* Navigation Top ***********/

var damper = false;

function chg_visibility( my_element, to_what )
{
	document.getElementById( my_element ).style.visibility = to_what;
}


function nt( my_action, my_nr )
{
	my_element =  element_id( my_nr );
	switch ( my_action )
	{
		case 'on':
			if ( damper )
			{
				window.clearTimeout( damper );
			}
			chg_visibility( my_element, 'visible' );
			for( i=1; i<6; i++ )
			{
				if ( i != my_nr )
				{
					other_element =  element_id( i );
					chg_visibility( other_element, 'hidden' );
				}
			}
		break;
		case 'off':
			damper = window.setTimeout( "chg_visibility( my_element, 'hidden' )", 500 );
		break;
	}
}

function element_id( my_nr )
{
	r = 'nt_sub' + my_nr + '_akt';
	return r;
}