// browsercheck
var newDHTML = (document.getElementById) ? true : false;

// init
gfx=new Array();
gfx_over=new Array();


// rollover
function setgfx(myElement, nr) {
	window.document.images[myElement].src = gfx[nr].src;
}

function rolldown(nr) {
	window.document.images[''+eval('"gfx_' + nr +'"')].src = gfx_over[nr].src;
}

function rollup(nr) {
	window.document.images[''+eval('"gfx_' + nr +'"')].src = gfx[nr].src;
}

//pre-load
function preload (idx,image_ref)
{
	gfx[idx] = new Image();
	gfx[idx].src = image_ref+'.gif';
	gfx_over[idx] = new Image();
	gfx_over[idx].src = image_ref+'_ov.gif';
}

// layers
function showLayer(layer_to_show){
	if (newDHTML) {
		if (document.getElementById(layer_to_show)) {
			document.getElementById(layer_to_show).style.display ="inline";
		}
	}
}

function hideLayer(layer_to_hide){
	if (newDHTML) {
		if (document.getElementById(layer_to_hide)) {
			document.getElementById(layer_to_hide).style.display ="none";
		}
	}
}

function myExpand(myLayer) {
	hideLayer('nav' + myLayer + 'a');
	showLayer('nav' + myLayer + 'b');
	showLayer('cont' + myLayer);
}

function myCollapse(myLayer) {
	showLayer('nav' + myLayer + 'a');
	hideLayer('nav' + myLayer + 'b');
	hideLayer('cont' + myLayer);
}

function myCollapseVideo(myLayer) {
	myCollapse(myLayer);
	hideLayer('left_video');
}

function myCollapseAudio(myLayer) {
	myCollapse(myLayer);
	hideLayer('left_audio');
}