var activehighlight = '1';
 var funzt;
 var highlightlaeuft = 0;
 function changehighlight()
 {
 if(activehighlight == '4')
 { show('highlight1'); return;}
 if(activehighlight == '3')
 { show('highlight4'); return;}
 if(activehighlight == '2')
 { show('highlight3'); return;}
 if(activehighlight == '1')
 { show('highlight2'); return;}
 }
 function startinterval() {
 if(highlightlaeuft == 0){
 funzt = window.setInterval(changehighlight, 5000);
 highlightlaeuft = 1;
 }
 }
 function endinterval() {
 clearInterval(funzt);
 highlightlaeuft = 0;
 }
 function show(highlight) {
 switch(highlight) {
 case 'highlight1':
 document.getElementById('highlight_01').style.display = 'block';
 document.getElementById('highlight_02').style.display = 'none';
 document.getElementById('highlight_03').style.display = 'none';
 document.getElementById('highlight_04').style.display = 'none';
 activehighlight = '1';
 break;
 case 'highlight2':
 document.getElementById('highlight_01').style.display = 'none';
 document.getElementById('highlight_02').style.display = 'block';
 document.getElementById('highlight_03').style.display = 'none';
 document.getElementById('highlight_04').style.display = 'none';
 activehighlight = '2';
 break;
 case 'highlight3':
 document.getElementById('highlight_01').style.display = 'none';
 document.getElementById('highlight_02').style.display = 'none';
 document.getElementById('highlight_03').style.display = 'block';
 document.getElementById('highlight_04').style.display = 'none';
 activehighlight = '3';
 break;
 case 'highlight4':
 document.getElementById('highlight_01').style.display = 'none';
 document.getElementById('highlight_02').style.display = 'none';
 document.getElementById('highlight_03').style.display = 'none';
 document.getElementById('highlight_04').style.display = 'block';
 activehighlight = '4';
 break;
 }
 }