js代码

<script>
	const NUMBER_OF_LEAVES = 15;
  const width=window.screen.width;
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');
    var image = document.createElement('img');
    image.src = 'images/cash' + randomInteger(3, 7) + '.png';
    leafDiv.style.top = "-100px";
    leafDiv.style.left = pixelValue(randomInteger(0, width));
    var spinAnimationName = (Math.random() < 0.5) ? 'clockwiseSpin' : 'counterclockwiseSpinAndFlip';
    leafDiv.style.webkitAnimationName = 'fade, drop';
    image.style.webkitAnimationName = spinAnimationName;
    var fadeAndDropDuration = durationValue(randomFloat(3, 9));
    var spinDuration = durationValue(randomFloat(3, 7));
    leafDiv.style.webkitAnimationDuration = fadeAndDropDuration + ', ' + fadeAndDropDuration;
    var leafDelay = durationValue(randomFloat(0, 0));
    leafDiv.style.webkitAnimationDelay = leafDelay + ', ' + leafDelay;
    image.style.webkitAnimationDuration = spinDuration;
    leafDiv.appendChild(image);
    return leafDiv;
}
window.addEventListener('load', init, false);
</script>