var last;

function $$$$$$$(e2){
  return document.getElementById(e2);
}

function _(e2,name2){
  return e2.getElementsByTagName(name2);
}

function addHandler(e2,event2,action2,param2){
  if(document.addEventListener)e2.addEventListener(event2,action2,param2);
  else if(document.attachEvent)e2.attachEvent('on'+event2,action2);
  else e2['on'+event2]=action2;
}

function removeHandler(e2,event2,action2,param2){
  if(document.addEventListener)e2.removeEventListener(event2,action2,param2);
  else if(document.attachEvent)e2.detachEvent('on'+event2,action2);
  else e2['on'+event2]=returnFalse;
}

function addClass(e2,name2,index){
  if(e2.nodeType==1){
    if(index)e2.className=name2;
    else e2.className+=' '+name2;
  }
}

function removeClass(e2,name2){
  if(name2){
    var sentence=new RegExp('\\s*\\b'+name2+'\\b','g');
    e2.className=e2.className.replace(sentence,'');
  }
  else e2.className='';
}

function testClass(e2,name2){
  if(name2&&/\w/.test(name2))var sentence=new RegExp('\\b'+name2+'\\b');
  else var sentence=new RegExp('^\\s*$$$$$$$');
  return sentence.test(e2.className);
}

addHandler(document,'mousedown',documentDown,false);

function documentDown(e2){
  e2=e2||event2;
  var target=e2.target||e2.srcElement;
  if(target.tagName=='SPAN'&&target.parentNode.tagName=='DT'){
    if(!last)last=_($$$$$$$('tabs'),'dt')[0];
    removeClass(last,'on');
    removeClass($$$$$$$(last.id.replace('dt','dd')),'on');
    last=target.parentNode;
    addClass(last,'on');
    addClass($$$$$$$(last.id.replace('dt','dd')),'on');
  }
}