function show_tab(nr,cnt){
      
      for(var a=0; a < cnt; a++){
        document.getElementById("links_" + a).className = 'temp_6_tab_left';
        document.getElementById("mitte_" + a).className = 'temp_6_tab';
        document.getElementById("rechts_" + a).className = 'temp_6_tab_right';
        
        document.getElementById("tab_" + a).style.visibility = "hidden";
      }
      
      document.getElementById("links_" + nr).className = 'temp_6_tab_left_akt';
      document.getElementById("mitte_" + nr).className = 'temp_6_tab_akt';
      document.getElementById("rechts_" + nr).className = 'temp_6_tab_right_akt';
      
      document.getElementById("tab_" + nr).style.visibility = "visible";
    }
  
    
    function show_img_tab(nr,cnt){
      
      for(var a=0; a < cnt; a++){
        document.getElementById("links_" + a).className = 'temp_15_tab_left';
        document.getElementById("mitte_" + a).className = 'temp_15_tab';
        document.getElementById("rechts_" + a).className = 'temp_15_tab_right';
        
        document.getElementById("tab_con_" + a).style.visibility = "hidden";
      }
      
      document.getElementById("links_" + nr).className = 'temp_15_tab_left_akt';
      document.getElementById("mitte_" + nr).className = 'temp_15_tab_akt';
      document.getElementById("rechts_" + nr).className = 'temp_15_tab_right_akt';
      
      document.getElementById("tab_con_" + nr).style.visibility = "visible";
      document.getElementById('img_1').src = "bilder/produkte/empty.jpg";
      document.getElementById('img_1').style.border = "solid #FFFFFF 0px"; 
    }