// JavaScript Document
var snowflake = "snow1.gif";
  var no = 12; // number of snowflakes on the screen
  var speed = 2; // smaller numbers make the snow fall faster
  var dx, xp, yp;    // coordinate and position variables
  var am, stx, sty;  // amplitude and step variables
  var obj, i, doc_width = 790, doc_height = 600;

  function winSize() {
          doc_width = window.innerWidth?window.innerWidth:document.body.clientWidth;
          doc_height = window.innerHeight?window.innerHeight:document.body.clientHeight;
          }

  dx = new Array();
  xp = new Array();
  yp = new Array();
  am = new Array();
  stx = new Array();
  sty = new Array();
  winSize();
  document.write("<STYLE type=\"text/css\">.flake {position:absolute;top:-200;}</STYLE>");
  for (i = 0; i < no; i++) {  
          dx[i] = 0;                        // set coordinate variables
          xp[i] = Math.random()*(doc_width-30) +10;  // 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
          document.write("<div id=\"dot"+ i +"\" class=\"flake\"><img src=\"");
          document.write(snowflake + "\" border=\"0\"></div>");
          }

  function snowMove(id,left,top) {
          obj = document.getElementById?document.getElementById(id).style:
                  document.all?document.all[id].style:
                  document.layers?document.layers[id]:null;
          if (obj) {
                  obj.left=left;
                  obj.top=top;
                  }
          }

  function snow() {
          winSize();
          doc_scroll = (window.pageYOffset!=null)?window.pageYOffset:document.body.scrollTop;
          for (i = 0; i < no; ++ i) {  // iterate for every dot
                  yp[i] += sty[i];
                  if (yp[i] > doc_height+doc_scroll-50) {
                          xp[i] = Math.random()*(doc_width-am[i]-30);
                          yp[i] = doc_scroll;
                          stx[i] = 0.02 + Math.random()/10;
                          sty[i] = 0.7 + Math.random();
                  }
                  dx[i] += stx[i];
                  snowMove("dot"+i,xp[i]+am[i]*Math.sin(dx[i]),yp[i]);
          }
          setTimeout("snow()", speed);
  }

  window.onload=snow;