function setOpacity(div, level) {
  var xdiv=document.getElementById(div);
  xdiv.style.opacity = level;
  xdiv.style.MozOpacity = level;
  xdiv.style.KhtmlOpacity = level;
  xdiv.style.filter = "alpha(opacity=" + (level * 100) + ");";
}

var duration = 1000;  /* 1000 millisecond fade = 1 sec */
var steps = 20;       /* number of opacity intervals   */
var delay = 5000;     /* 5 sec delay before fading out */

function fadeIn(div){
  document.getElementById(div).style.display='block';

  for (i = 0; i <= 1; i += (1 / steps)) {
    setTimeout("setOpacity('"+div+"', " + i + ")", i * duration);
  }
  setTimeout("fadeOut()", delay);
}

function fadeOut(div) {
  for (i = 0; i <= 1; i += (1 / steps)) {
    setTimeout("setOpacity('"+div+"', " + (1 - i) + ")", i * duration);
  }
  document.getElementById(div).style.display='none';
  setTimeout("fadeIn()", duration);
}

function hide(div) {
  var xdiv=document.getElementById(div);
  xdiv.style.opacity = 0.0;
  xdiv.style.MozOpacity = 0.0;
  xdiv.style.KhtmlOpacity = 0.0;
  xdiv.style.filter = "alpha(opacity=0);";
  xdiv.style.display='none';
}

function switchcontent(div) {
hide('services_intro');
hide('service_agreements');
hide('managed_services');
hide('computer_repair');

fadeIn(div);
}