function getWindowHeight() {
  var windowHeight=0;
  if (typeof(window.innerHeight)=='number') {
    windowHeight=window.innerHeight;
  }
  else {
    if (document.documentElement&&
      document.documentElement.clientHeight) {
        windowHeight=
          document.documentElement.clientHeight;
    }
    else {
      if (document.body&&document.body.clientHeight) {
        windowHeight=document.body.clientHeight;
      }
    }
  }
  return windowHeight;
}

function setFooter() {
  if (document.getElementById) {
    var windowHeight=getWindowHeight();
    if (windowHeight>0) {
	var headerHeight=
        document.getElementById('header').offsetHeight;
      var contentHeight=
        document.getElementById('main-content').offsetHeight;
      var footerElement=
        document.getElementById('footer');
      var footerHeight=footerElement.offsetHeight;
      if (windowHeight-(contentHeight+footerHeight+headerHeight)>=0) {
        footerElement.style.position='relative';
        footerElement.style.top=(windowHeight-
          (contentHeight+footerHeight+headerHeight))+'px';                
      }
      else {
        footerElement.style.position='static';
      }
    }
  }
}

function bottomFooter(){
      var footerElement=
        document.getElementById('footer');
    footerElement.style.position='absolute';
    footerElement.style.bottom='0';
    // detects the browser in an if statement  
}


//create onDomReady Event
window.onDomReady = DomReady;

//Setup the event
function DomReady(fn)
{
    //W3C
    if(document.addEventListener)
    {
        document.addEventListener("DOMContentLoaded", fn, false);
    }
    //IE
    else
    {
        document.onreadystatechange = function(){readyState(fn)}
    }
}

//IE execute function
function readyState(fn)
{
    //dom is ready for interaction
    if(document.readyState == "interactive")
    {
        fn();
    }
}

//execute as soon as DOM is loaded
window.onDomReady(onReady);

//do on ready
function onReady()
{
    bottomFooter();
    setFooter();
}

window.onload = function() {
    setFooter();
}

window.onresize = function() {
  setFooter();
}