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-----Mã code như sau----------

<script>
//var pictureSrc = ‘http://img244.imageshack.us/img244/1024/snowbw4.gif’; //the location of the snowflakes//Noel
var pictureSrc = ‘http://s351.photobucket.com/albums/q463/web_tgth/th_Hoadao.gif’; //the location of the snowflakes//Xuân
var pictureWidth = 20;            //the width of the snowflakes
var pictureHeight = 20;          //the height of the snowflakes
var numFlakes = 10;              //the number of snowflakes
var downSpeed = 0.01;            //the falling speed of snowflakes (portion of screen per 100 ms)
var lrFlakes = 10;                //the speed that the snowflakes should swing from side to side


if( typeof( numFlakes ) != ‘number’ || Math.round( numFlakes ) != numFlakes || numFlakes < 1 ) { numFlakes = 10; }

//draw the snowflakes
for( var x = 0; x < numFlakes; x++ ) {
if( document.layers ) { //releave NS4 bug
document.write(‘<layer id=”snFlkDiv’+x+’”><img src=”’+pictureSrc+’” height=”’+pictureHeight+’” width=”’+pictureWidth+’” alt=”*” border=”0”></layer>’);
} else {
document.write(‘<div style=”position:absolute;” id=”snFlkDiv’+x+’”><img src=”’+pictureSrc+’” height=”’+pictureHeight+’” width=”’+pictureWidth+’” alt=”*” border=”0”></div>’);
}
}

//calculate initial positions (in portions of browser window size)
var xcoords = new Array(), ycoords = new Array(), snFlkTemp;
for( var x = 0; x < numFlakes; x++ ) {
xcoords[x] = ( x + 1 ) / ( numFlakes + 1 );
do { snFlkTemp = Math.round( ( numFlakes – 1 ) * Math.random() );
} while( typeof( ycoords[snFlkTemp] ) == ‘number’ );
ycoords[snFlkTemp] = x / numFlakes;
}

//now animate
function flakeFall() {
if( !getRefToDivNest(‘snFlkDiv0’) ) { return; }
var scrWidth = 0, scrHeight = 0, scrollHeight = 0, scrollWidth = 0;
//find screen settings for all variations. Doing this every time allows for resizing and scrolling
if( typeof( window.innerWidth ) == ‘number’ ) { scrWidth = window.innerWidth; scrHeight = window.innerHeight; } else {
if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
  scrWidth = document.documentElement.clientWidth; scrHeight = document.documentElement.clientHeight; } else {
  if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
  scrWidth = document.body.clientWidth; scrHeight = document.body.clientHeight; } } }
if( typeof( window.pageYOffset ) == ‘number’ ) { scrollHeight = pageYOffset; scrollWidth = pageXOffset; } else {
if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) { scrollHeight = document.body.scrollTop; scrollWidth = document.body.scrollLeft; } else {
  if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) { scrollHeight = document.documentElement.scrollTop; scrollWidth = document.documentElement.scrollLeft; } }
}
//move the snowflakes to their new position
for( var x = 0; x < numFlakes; x++ ) {
if( ycoords[x] * scrHeight > scrHeight – pictureHeight ) { ycoords[x] = 0; }
var divRef = getRefToDivNest(‘snFlkDiv’+x); if( !divRef ) { return; }
if( divRef.style ) { divRef = divRef.style; } var oPix = document.childNodes ? ‘px’ : 0;
divRef.top = ( Math.round( ycoords[x] * scrHeight ) + scrollHeight ) + oPix;
divRef.left = ( Math.round( ( ( xcoords[x] * scrWidth ) – ( pictureWidth / 2 ) ) + ( ( scrWidth / ( ( numFlakes + 1 ) * 4 ) ) * ( Math.sin( lrFlakes * ycoords[x] ) – Math.sin( 3 * lrFlakes * ycoords[x] ) ) ) ) + scrollWidth ) + oPix;
ycoords[x] += downSpeed;
}}
//DHTML handlers
function getRefToDivNest(divName) {
if( document.layers ) { return document.layers[divName]; } //NS4
if( document[divName] ) { return document[divName]; } //NS4 also
if( document.getElementById ) { return document.getElementById(divName); } //DOM (IE5+, NS6+, Mozilla0.9+, Opera)
if( document.all ) { return document.all[divName]; } //Proprietary DOM – IE4
return false;
}
window.setInterval(‘flakeFall();’,100);</script>

------------Hết------------

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