css3流星雨动画

作者: LI_4058 | 来源:发表于2018-06-29 14:29 被阅读0次

网页高级知识点（三）
css3流星雨动画
07day
08_dayCSS动画
CSS3 动画
CSS3 动画
css3动画
纯CSS3绘制的逼真，呆萌，超酷的CSS3动画
关于js动画和css3动画的差异性你了解吗？请简单谈一下
过度动画

下面是页面源码：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        html,body{
            width: 100%;height: 100%;margin: 0;overflow: hidden;background: linear-gradient(rgba(0,0,0,.8),rgba(0,0,0,.4));
        }
        #stars{
            margin: 0 auto;max-width: 1600px;position: fixed;top: 0;left: 0;right: 0;bottom: 0;z-index: 2;
        }
        .star{
            display: block;width: 1px;background: transparent;position: relative;opacity: 0;
            /*过渡动画*/
            animation: star-fall 3s linear infinite;
            -webkit-animation: star-fall 3s linear infinite;
            -moz-animation: star-fall 3s linear infinite;
        }
        .star:after {
            content: '';
            display: block;
            border: 0px solid #fff;
            border-width: 0px 90px 2px 90px;
            border-color: transparent transparent transparent rgba(255, 255, 255, .5);
            box-shadow: 0 0 1px 0 rgba(255, 255, 255, .1);
            /*变形*/
            transform: rotate(-45deg) translate3d(1px, 3px, 0);
            -webkit-transform: rotate(-45deg) translate3d(1px, 3px, 0);
            -moz-transform: rotate(-45deg) translate3d(1px, 3px, 0);
            transform-origin: 0% 100%;
            -webkit-transform-origin: 0% 100%;
            -moz-transform-origin: 0% 100%;
        }
        @keyframes star-fall {
            0% {
                opacity: 0;
                transform: scale(0.5) translate3d(0, 0, 0);
                -webkit-transform: scale(0.5) translate3d(0, 0, 0);
                -moz-transform: scale(0.5) translate3d(0, 0, 0);
            }
            50% {
                opacity: 1;
                transform: translate3d(-200px, 200px, 0);
                -webkit-transform: translate3d(-200px, 200px, 0);
                -moz-transform: translate3d(-200px, 200px, 0);
            }
            100% {
                opacity: 0;
                transform: scale(1.2) translate3d(-300px, 300px, 0);
                -webkit-transform: scale(1.2) translate3d(-300px, 300px, 0);
                -moz-transform: scale(1.2) translate3d(-300px, 300px, 0);
            }
        }
    </style>
</head>
<body>
    <div id="stars">
        <div class="star" style="top: 0px;left: 500px"></div>
    </div>
<script>
    var stars = document.getElementById('stars')

    // js随机生成流星
    for (var j=0;j<30;j++) {
        var newStar = document.createElement("div")
        newStar.className = "star"
        newStar.style.top = randomDistance(500, -100) + 'px'
        newStar.style.left = randomDistance(1300, 300) + 'px'
        stars.appendChild(newStar)
    }

    // 封装随机数方法
    function randomDistance (max, min) {
        var distance = Math.floor(Math.random() * (max - min + 1) + min)
        return distance
    }
    var star = document.getElementsByClassName('star')

    // 给流星添加动画延时
    for (var i = 0, len = star.length; i < len; i++)
    {
        star[i].style.animationDelay = i % 6 == 0 ? '0s' : i * 0.8 + 's'
    }
</script>
</body>
</html>