HTML5 animation (1): Implement falling leaves,

HTML5 animation (1): Implement falling leaves,

Implementation Effect (fallen leaves ):

Html code:

<! DOCTYPE html> 
Css code:
body{    background-color: #4E4226;}#container {    position: relative;    height: 700px;    width: 500px;    margin: 10px auto;    overflow: hidden;    border: 4px solid #5C090A;    background: #4E4226 url('images/backgroundLeaves.jpg') no-repeat top left;}#leafContainer {    position: absolute;    width: 100%;    height: 100%;}#message{    position: absolute;    top: 160px;    width: 100%;    height: 300px;    background:transparent url('images/textBackground.png') repeat-x center;    color: #5C090A;    font-size: 220%;    font-family: 'Georgia';    text-align: center;    padding: 20px 10px;    -webkit-box-sizing: border-box;    -webkit-background-size: 100% 100%;    z-index: 1;}em {    font-weight: bold;    font-style: normal;}#leafContainer > div {    position: absolute;    width: 100px;    height: 100px;    -webkit-animation-iteration-count: infinite;    -webkit-animation-direction: normal;    -webkit-animation-timing-function: linear;}#leafContainer > div > img {     position: absolute;     width: 100px;     height: 100px;     -webkit-animation-iteration-count: infinite;     -webkit-animation-direction: alternate;     -webkit-animation-timing-function: ease-in-out;     -webkit-transform-origin: 50% -100%;}@-webkit-keyframes fade{    0%   { opacity: 1; }    95%  { opacity: 1; }    100% { opacity: 0; }}@-webkit-keyframes drop{    0%   { -webkit-transform: translate(0px, -50px); }    100% { -webkit-transform: translate(0px, 650px); }}@-webkit-keyframes clockwiseSpin{    0%   { -webkit-transform: rotate(-50deg); }    100% { -webkit-transform: rotate(50deg); }}@-webkit-keyframes counterclockwiseSpinAndFlip {    0%   { -webkit-transform: scale(-1, 1) rotate(50deg); }    100% { -webkit-transform: scale(-1, 1) rotate(-50deg); }}
Js Code:
const NUMBER_OF_LEAVES = 30;function init(){    var container = document.getElementById('leafContainer');    for (var i = 0; i < NUMBER_OF_LEAVES; i++) {        container.appendChild(createALeaf());    }}function randomInteger(low, high){    return low + Math.floor(Math.random() * (high - low));}function randomFloat(low, high){    return low + Math.random() * (high - low);}function pixelValue(value){    return value + 'px';}function durationValue(value){    return value + 's';}function createALeaf(){    var leafDiv = document.createElement('div');    leafDiv.style.top = "-100px";    leafDiv.style.left = pixelValue(randomInteger(0, 500));    leafDiv.style.webkitAnimationName = 'fade, drop';    var fadeAndDropDuration = durationValue(randomFloat(5, 11));    leafDiv.style.webkitAnimationDuration = fadeAndDropDuration + ', ' + fadeAndDropDuration;    var leafDelay = durationValue(randomFloat(0, 5));    leafDiv.style.webkitAnimationDelay = leafDelay + ', ' + leafDelay;        var image = document.createElement('img');    image.src = 'images/realLeaf' + randomInteger(1, 5) + '.png';    var spinAnimationName = (Math.random() < 0.5) ? 'clockwiseSpin' : 'counterclockwiseSpinAndFlip';    image.style.webkitAnimationName = spinAnimationName;    var spinDuration = durationValue(randomFloat(4, 8));    image.style.webkitAnimationDuration = spinDuration;    leafDiv.appendChild(image);    return leafDiv;}window.addEventListener('load', init, false);
Address: http://www.html5tricks.com/css3-fall-leaves.html