function display_variant(id)
        {
            if (!id) id = $('product_variant').value;
            variant_ids.each(function(vid){
                if ((vid>0) && ($('variant_'+vid).style.display!='none'))
                {
                    new Effect.Fade('variant_'+vid, {duration:0.3});
                    if ($('variant_'+vid+'_label'))
                        Element.hide('variant_'+vid+'_label');
                    if ($('variant_'+vid+'_label_kal'))
                        Element.hide('variant_'+vid+'_label_kal');
                    if ($('variant_'+vid+'_kal'))
                        Element.hide('variant_'+vid+'_kal');                        
                }
            });
            new Effect.Appear('variant_'+id, {duration:0.3, queue:'end'});
            if ($('variant_'+id+'_label'))
                Element.show('variant_'+id+'_label');
            if ($('variant_'+id+'_label_kal'))
                Element.show('variant_'+id+'_label_kal');
            if ($('variant_'+id+'_kal'))
                Element.show('variant_'+id+'_kal');                
            /*
            if (has_kalendarium)
            {
                backup = $('variant_'+id).src;
                Event.observe('product_variant_image', 'mouseover', function(e) { $('variant_'+id).hide(); $('variant_'+id+'_kal').show(); });
                Event.observe('product_variant_image', 'mouseout', function(e) { $('variant_'+id+'_kal').hide(); $('variant_'+id).show();  });
            }*/
            $('product_variant_code').innerHTML = variants[id][3];
            if ($('product_variant_price')) $('product_variant_price').innerHTML = variants[id][2];
            $('product_variant_variant').innerHTML = variants[id][4];
            if ($('product_variant_stock'))
                $('product_variant_stock').href = product_stock_url+'?code='+variants[id][3];
            $('product_variant_id').value = variants[id][0];
            if ($('variants_li_'+id))
                $('variants_li_'+id).className='active';
                
            /* STAV SKLADU */
            $$('tr.stavskladu').each(function(radek){ radek.hide(); });
            if ($('stava_'+variants[id][3])) $('stava_'+variants[id][3]).show();
            if ($('stavb_'+variants[id][3])) $('stavb_'+variants[id][3]).show();   
            if ($('stavc_'+variants[id][3])) $('stavc_'+variants[id][3]).show();
        }
        
        function display_image(src)
        {
            if (!more_images[src])
            {
                more_images[src] = document.createElement('img');
                more_images[src].src = src;
                more_images[src].style.display = 'none';
                $('product_variant_images').appendChild(more_images[src]);
            }
            $$('#product_variant_images img').each(function(image){
                if (image.style.display!='none')
                {
                    new Effect.Fade(image, {duration:0.3});
                }
            });
            new Effect.Appear(more_images[src], {duration:0.3, queue:'end'});
        }        
        
    function checkStock(inStock)
    {
        weWant = $('stock_num').value;
        if (weWant<1)
        {
            Element.hide('stock_err');
            Element.hide('stock_ok');
            alert('Zadejte čístlo větší než 0');
        }
        else if (inStock>=weWant)
        {
            $('stock_ok_no').innerHTML = weWant;
            Element.show('stock_ok');
            Element.hide('stock_err');
        }
        else
        {
            $('stock_err_no').innerHTML = weWant;
            Element.show('stock_err');
            Element.hide('stock_ok');
        }
    }