Trước tiên các bạn vào Chủ đề => Chỉnh sửa HTML => Crtl + F => gõ <head> và past đoạn code bên dưới ngay sau thẻ <head>
<script type='text/javascript'> //<![CDATA[ var pictureSrc ="http://imagizer.imageshack.us/a/img922/4604/a9gdFv.png"; //Link ảnh hoa muốn hiển thị trên web var pictureWidth = 15; //Chiều rộng của hoa mai or đào var pictureHeight = 15; //Chiều cao của hoa mai or đào var numFlakes = 10; //Số bông hoa xuất hiện cùng một lúc trên trang web var downSpeed = 0.01; //Tốc độ rơi của hoa var lrFlakes = 10; //Tốc độ các bông hoa giao động từ bên trai sang bên phải và ngược lại 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+'"><imgsrc="'+pictureSrc+'" height="'+pictureHeight+'"width="'+pictureWidth+'" alt="*" border="0"></layer>'); } else { document.write('<div style="position:absolute; z-index:9999;"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>- Sau đó muốn trang trí 2 câu chúc 2 bên thì Crtl + F đến thẻ <body> - không có thì tìm thẻ </body> và paste đoạn code dưới vào trước thẻ đó.
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