function showTab(i) {
  if (i==2) {
  document.getElementById('t2').className = 't_updated_on';
  document.getElementById('t1').className = 't_firstword_off';
  document.getElementById('d1').style.display = 'none';
  document.getElementById('d2').style.display = 'block';
  } else {
  document.getElementById('t1').className = 't_firstword_on';
  document.getElementById('t2').className = 't_updated_off';
  document.getElementById('d2').style.display = 'none';
  document.getElementById('d1').style.display = 'block';
 }
}

var i=1;
var t;

function timedTabs() {
	showTab(i);
	i=i+1;
	t=setTimeout("timedTabs()",6000);
	if (i==3) i=1;
}

function clickTab(i) {
  stopTimedTabs();
  showTab(i);
}

function stopTimedTabs() {
  clearTimeout(t);
  document.getElementById('tabsButton').className = 'play';
}

function playTimedTabs() {
  timedTabs();
  document.getElementById('tabsButton').className = 'pause';
}

function doButton() {
  if (document.getElementById('tabsButton').className == 'pause') {
    stopTimedTabs();
  } else {
    playTimedTabs();
  }
}