var no = 7; // snow number
var speed = 40; // smaller number moves the snow faster
var snowflake = "/images/snowflake.gif";
var ns4up = (document.layers) ? 1 : 0; // browser sniffer
var ie4up = (document.all) ? 1 : 0;
var dx, xp, yp; // coordinate and position variables
var am, stx, sty; // amplitude and step variables
var i, doc_width = 800, doc_height = 400;

if (ns4up) {
   doc_width = self.innerWidth;
   doc_height = self.innerHeight;
} else if (ie4up) {
   doc_width = document.body.clientWidth;
   doc_height = document.body.clientHeight;
}

dx = new Array();
xp = new Array();
yp = new Array();
am = new Array();
stx = new Array();
sty = new Array();

for (i = 0; i < no; ++ i) { 
   dx[i] = 0; // set coordinate variables
   xp[i] = Math.random()*(doc_width-50); // set position variables
   yp[i] = Math.random()*doc_height;
   am[i] = Math.random()*20; // set amplitude variables
   stx[i] = 0.02 + Math.random()/10; // set step variables
   sty[i] = 0.7 + Math.random(); // set step variables
   if (ns4up) { // set layers
		document.write("<layer name=\"dot"+ i +"\" left=\"15\" ");
		document.write("top=\"15\" visibility=\"show\"><img src=\"");
		document.write(snowflake + "\" border=\"0\"></layer>");
   } else if (ie4up) {
		document.write("<div id=\"dot"+ i +"\" style=\"POSITION: ");
		document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");
		document.write("visible; TOP: 15px; LEFT: 15px;\"><img src=\"");
		document.write(snowflake + "\" border=\"0\"></div>");
   }
}

function snowNS() { // Netscape main animation function
   for (i = 0; i < no; ++ i) { // iterate for every dot
      yp[i] += sty[i];

      if (yp[i] > doc_height-50) {
         xp[i] = Math.random()*(doc_width-am[i]-30);
         yp[i] = 0;
         stx[i] = 0.02 + Math.random()/10;
         sty[i] = 0.7 + Math.random();
         doc_width = self.innerWidth;
         doc_height = 800;
      }
      
      dx[i] += stx[i];
      document.layers["dot"+i].top = yp[i];
      document.layers["dot"+i].left = xp[i] + am[i]*Math.sin(dx[i]);
   }
   setTimeout("snowNS()", speed);
}

function snowIE() { // IE main animation function
   for (i = 0; i < no; ++ i) { // iterate for every dot
      yp[i] += sty[i];
      if (yp[i] > doc_height-50) {
         xp[i] = Math.random()*(doc_width-am[i]-30);
         yp[i] = 0;
         stx[i] = 0.02 + Math.random()/10;
         sty[i] = 0.7 + Math.random();
         doc_width = document.body.clientWidth;
         doc_height = 800;
      }
      dx[i] += stx[i];
      document.all["dot"+i].style.pixelTop = yp[i];
      document.all["dot"+i].style.pixelLeft = xp[i] + am[i]*Math.sin(dx[i]);
   }
   setTimeout("snowIE()", speed);
}

if (ns4up) {
   snowNS();
} else if (ie4up) {
   snowIE();
}