function Is ()
{   // convert all characters to lowercase to simplify testing
    var agt=navigator.userAgent.toLowerCase()

    // --- BROWSER VERSION ---
    this.major = stringToNumber(navigator.appVersion)
    this.minor = parseFloat(navigator.appVersion)

    this.nav  = ((agt.indexOf('mozilla')!=-1) && ((agt.indexOf('spoofer')==-1)
                && (agt.indexOf('compatible') == -1)))
    this.nav2 = (this.nav && (this.major == 2))
    this.nav3 = (this.nav && (this.major == 3))
    this.nav4 = (this.nav && (this.major == 4))
	
	//Netscape 6
	this.nav5 =	(this.nav && (this.major == 5))
	this.nav6 = (this.nav && (this.major == 5))
	this.gecko = (this.nav && (this.major >= 5))

    this.ie   = (agt.indexOf("msie") != -1)
    this.ie3  = (this.ie && (this.major == 2))
    this.ie4  = (this.ie && (this.major == 3))
    this.ie5  = (this.ie && (this.major == 4))


    this.opera = (agt.indexOf("opera") != -1)
     
    this.nav4up = this.nav && (this.major >= 4)
    this.ie4up  = this.ie  && (this.major >= 4)
}

var is = new Is();

function getElt () 
{ if (is.nav4)
  {
    var currentLayer = document.layers[getElt.arguments[0]];
    for (var i=1; i<getElt.arguments.length && currentLayer; i++)
    {   currentLayer = currentLayer.document.layers[getElt.arguments[i]];
    }
    return currentLayer;
  } 
  else if(document.getElementById && document.getElementsByName)
  { 
    var name = getElt.arguments[getElt.arguments.length-1];
    if(document.getElementById(name))                      //First try to find by id
       return document.getElementById(name);
    else if (document.getElementsByName(name))             //Then if that fails by name
	   return document.getElementsByName(name)[0];
  }
  else if (is.ie4up) {
    var elt = eval('document.all.' + getElt.arguments[getElt.arguments.length-1]);
    return(elt);
  }

}

function showElt(elt)
{
	setEltVisibility(elt,'visible');
}

function hideElt(elt)
{
	setEltVisibility(elt, 'hidden');
}

/* value must be "visible", "hidden", or "inherit".
   These values work on Nav4, Gecko and IE for setting visibility.
*/
function setEltVisibility (elt, value)
{  if (is.nav4) elt.visibility = value;
   else if (elt.style) elt.style.visibility = value;
}

function getEltPageLeft(elt) {
  var x;

  if (is.nav4)
    return elt.pageX;
  if (is.ie4up || is.opera) { /* DBW 10/17/01 */
    x = 0;
    while (elt.offsetParent != null) {
      x += elt.offsetLeft;
      elt = elt.offsetParent;
    }
    x += elt.offsetLeft;
    return x;
  }
  if (is.gecko) {
    x = 0;
    while (elt.offsetParent != null) {
      x += elt.offsetLeft;
      elt = elt.offsetParent;
    }
    x += elt.offsetLeft;
    return x;
  }
  return -1;
}

/* xbrowser pageY equivalent */
function getEltPageTop(elt) {
  var y;

  if (is.nav4)
    return elt.pageY;
  if (is.ie4up || is.opera) { /* DBW 10/17/01 */
    y = 0;
    while (elt.offsetParent != null) {
      y += elt.offsetTop;
      elt = elt.offsetParent;
    }
    y += elt.offsetTop;
    
    /* Need to add margin-top set on the body element in Mac MSIE5 */
    if (is.mac && is.ie5) {
    	var marginTop = document.body.currentStyle.marginTop
    	if (marginTop != '') y += stringToNumber(marginTop)
    }

    return y;
  }
  if (is.gecko) {
    y = 0;
    while (elt.offsetParent != null) {
      y += elt.offsetTop;
      elt = elt.offsetParent;
    }
    y += elt.offsetTop;
    return y;
  }
  return -1;
}

/* Returns width of elt in pixels. */
function getEltWidth(elt) {

  if (is.nav4) {
    if (elt.document.width)
      return elt.document.width;
    else
      return elt.clip.right - elt.clip.left;
  }
  if (is.ie4up) {
    if (elt.style.pixelWidth)
      return elt.style.pixelWidth;

    else
      return elt.offsetWidth;
  }
  if (is.gecko) {
    if (elt.style.width)
      return stringToNumber(elt.style.width);
    else
      return stringToNumber(elt.offsetWidth);
  }
  /* DBW 10/17/01 */
  if (is.opera) {
  	return elt.style.pixelWidth
  }
  return -1;
}

/* Returns height of elt in pixels. */
function getEltHeight(elt) {
  if (is.nav4) {
    if (elt.document.height)
      return elt.document.height;
    else
      return elt.clip.bottom - elt.clip.top;
  }
  if (is.ie4up) {
    if (elt.style.pixelHeight)
      return elt.style.pixelHeight;
    else
      return elt.clientHeight;
  }
  if (is.gecko) {
    if (elt.style.height)
      return stringToNumber(elt.style.height);
    else
      return stringToNumber(elt.offsetHeight);
  }
  /* DBW 10/17/01 */
  if (is.opera) {
  	return elt.style.pixelHeight
  }
  return -1;
}

/* Returns left edge of elt in pixels. */
function getEltLeft (elt) {
  if (is.nav4)     return (elt.left);
  else if (is.ie4up) return (elt.offsetLeft);
  else if (is.gecko) return stringToNumber(elt.offsetLeft);
}

/* Returns top edge of elt in pixels. */
function getEltTop (elt) 
{ if (is.nav4)     return (elt.top);
  else if (is.ie4up) return (elt.offsetTop);
  else if (is.gecko) return stringToNumber(elt.offsetTop);
}

function moveEltTo (elt, x, y) 
{ if (is.nav4) elt.moveTo(x, y);
  else if (is.ie4up || is.opera) {
    elt.style.pixelLeft = x;
    elt.style.pixelTop  = y;
  }
  else if (is.gecko) {
    elt.style.left = x + 'px';
    elt.style.top  = y+ 'px';
  }
}

function setEltZIndex (elt, z) 
{ if (is.nav4) elt.zIndex = z;
  else if (elt.style) elt.style.zIndex = z;
}

function stringToNumber(s)
{
   return parseInt(('0' + s), 10)
}