Cambia
Código Javascript
:
Ver original<body onload="new Accordian('basic-accordian',5,'header_highlight');">
por esto:
Código Javascript
:
Ver original<body onload="new Accordian('basic-accordian',5,'header_highlight');(function(h,c){h.classList.remove('header_highlight');c.style.height=0;c.style.display='none'})(document.getElementById('test-header'),document.getElementById('test-content'))">