function switch_image(number) {
         //alert(image);
         document.getElementById('bild'+number).className = 'active';
         this.document.className = 'active';
         document.getElementById('boxcontent'+number).className = 'active';
         document.getElementById('quicklinks_'+number).className = 'qactive';

         if(number==1) {
           document.getElementById('bild2').className = 'inactive';
           document.getElementById('bild3').className = 'inactive';
           document.getElementById('boxcontent2').className = 'inactive';
           document.getElementById('boxcontent3').className = 'inactive';
           document.getElementById('quicklinks_2').className = 'qinactive';
           document.getElementById('quicklinks_3').className = 'qinactive';
         } else if(number==2) {
           document.getElementById('bild1').className = 'inactive';
           document.getElementById('bild3').className = 'inactive';
           document.getElementById('boxcontent1').className = 'inactive';
           document.getElementById('boxcontent3').className = 'inactive';
           document.getElementById('quicklinks_1').className = 'qinactive';
           document.getElementById('quicklinks_3').className = 'qinactive';
         } else {
           document.getElementById('bild1').className = 'inactive';
           document.getElementById('bild2').className = 'inactive';
           document.getElementById('boxcontent1').className = 'inactive';
           document.getElementById('boxcontent2').className = 'inactive';
           document.getElementById('quicklinks_1').className = 'qinactive';
           document.getElementById('quicklinks_2').className = 'qinactive';
         }

}