JS配合CSS3实现动画和拖动小星星小Demo

先看一下实现的效果~

哈哈 没关系哈，这个动图是有点小，但是你也能看得清对吧~

首先处理右下角的文字掉落
先看html

<p>
        <span>我</span>
        <span>是</span>
        <span>一</span>
        <span>个</span>
        <span>p</span>
        <span>标</span>
        <span>签</span>
    </p>

CSS

        p {
   
            line-height: 60px;
            background-color: #ccc;
            width: 300px;
            margin: 100px auto;
            text-align: center;
            position: fixed;
            bottom: -50px;
            right: 100px;
        }

        span {
   
            animation: down 2s infinite;
            display: inline-block;
            position: relative;
            font-weight: bold;
            font-size: 28px;
        }

        @keyframes down {
   
            0% {
   
                transform: translateY(-360px);
            }
            100% {
   
                transform: translateY(0);
            }
        }

JS

    let spans = document.getElementsByTagName('span')
     let p = document.getElementsByTagName('p')[0]
         //鼠标经干改变颜色 
        p.addEventListener('mouseover', function (e) {
   
            if (e.target.nodeName.toLowerCase() == 'span') {
   
                this.style.color = 'rgba(' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',0.8)';
                e.target.style.color = 'rgba(' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',0.8)';
            }
        })
        let s = 0
        for (let i = 0; i < spans.length; i++) {
   
            s += .1
            //动画延迟事件
            spans[i].style['animation-delay'] = `${
     s}s`;
        }

小星星动画
HTML

    生成几个小星星呢 <input type="text"> <button>生成</button>
    <div class="div"></div>

CSS

.div {
   
            box-sizing: inherit;
            position: absolute;
            left: 0;
            top: 0;
            text-align: left;
            width: 100%;
            height: 100%;
            background-color: #ccc;
            margin: 0 auto;
            display: none;
        }

        .div>img {
   
            width: 30px;
            height: 30px;
            position: absolute;

        }

        .div>img:nth-child(1) {
   
            transition: all 100ms ease 1ms;
            z-index: 10;
        }

        .div>img:nth-child(2) {
   
            transition: all 100ms ease 2ms;
            z-index: 9;
        }

        .div>img:nth-child(3) {
   
            transition: all 100ms ease 3ms;
            z-index: 8;
        }

        .div>img:nth-child(4) {
   
            transition: all 100ms ease 4ms;
            z-index: 7;
        }

        .div>img:nth-child(5) {
   
            transition: all 100ms ease 5ms;
            z-index: 6;
        }

        .div>img:nth-child(6) {
   
            transition: all 100ms ease 6ms;
            z-index: 5;
        }

        .div>img:nth-child(7) {
   
            transition: all 100ms ease 7ms;
            z-index: 4;
        }

        .div>img:nth-child(8) {
   
            transition: all 100ms ease 8ms;
            z-index: 3;
        }

        .div>img:nth-child(9) {
   
            transition: all 100ms ease 9ms;
            z-index: 2;
        }

        .div>img:nth-child(10) {
   
            transition: all 100ms ease 10ms;
            z-index: 1;
        }

JS

        let divBox = document.getElementsByClassName('div')[0]
        let inp = document.getElementsByTagName('input')[0]
        let btn = document.getElementsByTagName('button')[0]
        //防止多次刷新页面dom
        let flag = true；
        //存储输入的数量
        let num;
        //鼠标划入
        divBox.addEventListener('mouseover', function (e) {
   
            let x = e.clientX
            let y = e.clientY
            if (flag) {
   
                let HtmlStr = '';
                for (let i = 0; i < num; i++) {
   
                //例用 ES6 字符串拼接
                    HtmlStr += `<img class="img${
     i}" src="./xingxing.png" alt="">`
                }
                this.innerHTML = HtmlStr
                //关闭flag
                flag = false
            }
            for (let i = 0; i < num; i++) {
   
                let classImg = document.getElementsByClassName(`img${
     i}`)[0]
                //定位 赋值
                classImg.style.top = y - 15 + 'px'
                classImg.style.left = x - 15 + 'px'
            }
            e.preventDefault()
        })
        //移动事件
        divBox.addEventListener('mousemove', function (e) {
   
            let x = e.clientX
            let y = e.clientY
            if (flag) {
   
                let HtmlStr = '';
                for (let i = 0; i < num; i++) {
   
                    HtmlStr += `<img class="img${
     i}" src="./xingxing.png" alt="">`
                }
                this.innerHTML = HtmlStr
                flag = false
            }
            for (let i = 0; i < num; i++) {
   
                let classImg = document.getElementsByClassName(`img${
     i}`)[0]
                classImg.style.top = y - 15 + 'px'
                classImg.style.left = x - 15 + 'px'
            }
            e.preventDefault()
        })
        //点击按钮判断
        btn.addEventListener('click', function () {
   
            //不是空不是非数字
            if (!isNaN(inp.value) && inp.value != '') {
   
            //数字大于0小于等于10
                if (inp.value > 10 || inp.value <= 0) {
   
                    window.alert('请输入小于十大于零')
                }
                num = inp.value
                divBox.style.display = 'block'
            } else {
   
                window.alert('请输入数字')
                return
            }
        })

全部代码

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>小星星</title>
    <style>
        * {
    
            padding: 0;
            margin: 0;
        }

        html,
        body {
    
            height: 100%;
            width: 100%;
            overflow: hidden;
            text-align: center;
        }

        p {
    
            line-height: 60px;
            background-color: #ccc;
            width: 300px;
            margin: 100px auto;
            text-align: center;
            position: fixed;
            bottom: -50px;
            right: 100px;
        }

        span {
    
            animation: down 2s infinite;
            display: inline-block;
            position: relative;
            font-weight: bold;
            font-size: 28px;
        }

        @keyframes down {
    
            0% {
    
                transform: translateY(-360px);
            }

            100% {
    
                transform: translateY(0);
            }
        }

        .div {
    
            box-sizing: inherit;
            position: absolute;
            left: 0;
            top: 0;
            text-align: left;
            width: 100%;
            height: 100%;
            background-color: #ccc;
            margin: 0 auto;
            display: none;
        }

        .div>img {
    
            width: 30px;
            height: 30px;
            position: absolute;

        }

        .div>img:nth-child(1) {
    
            transition: all 100ms ease 1ms;
            z-index: 10;
        }

        .div>img:nth-child(2) {
    
            transition: all 100ms ease 2ms;
            z-index: 9;
        }

        .div>img:nth-child(3) {
    
            transition: all 100ms ease 3ms;
            z-index: 8;
        }

        .div>img:nth-child(4) {
    
            transition: all 100ms ease 4ms;
            z-index: 7;
        }

        .div>img:nth-child(5) {
    
            transition: all 100ms ease 5ms;
            z-index: 6;
        }

        .div>img:nth-child(6) {
    
            transition: all 100ms ease 6ms;
            z-index: 5;
        }

        .div>img:nth-child(7) {
    
            transition: all 100ms ease 7ms;
            z-index: 4;
        }

        .div>img:nth-child(8) {
    
            transition: all 100ms ease 8ms;
            z-index: 3;
        }

        .div>img:nth-child(9) {
    
            transition: all 100ms ease 9ms;
            z-index: 2;
        }

        .div>img:nth-child(10) {
    
            transition: all 100ms ease 10ms;
            z-index: 1;
        }
    </style>
</head>

<body>
    <img src="" alt="">
    生成几个小星星呢 <input type="text"> <button>生成</button>
    <div class="div">
    </div>
    <p>
        <span>我</span>
        <span>是</span>
        <span>一</span>
        <span>个</span>
        <span>p</span>
        <span>标</span>
        <span>签</span>
    </p>
    <script>
        let spans = document.getElementsByTagName('span')
        let divBox = document.getElementsByClassName('div')[0]
        let inp = document.getElementsByTagName('input')[0]
        let btn = document.getElementsByTagName('button')[0]


        let s = 0
        for (let i = 0; i < spans.length; i++) {
    
            s += .1
            spans[i].style['animation-delay'] = `${
      s}s`;
        }


        let p = document.getElementsByTagName('p')[0]
        p.addEventListener('mouseover', function (e) {
    
            if (e.target.nodeName.toLowerCase() == 'span') {
    
                this.style.color = 'rgba(' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',0.8)';
                e.target.style.color = 'rgba(' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',' + Math.floor(Math.random() * 255) + ',0.8)';
            }
        })

        let flag = true
        let num;
        divBox.addEventListener('mouseover', function (e) {
    
            let x = e.clientX
            let y = e.clientY
            if (flag) {
    
                let HtmlStr = '';
                for (let i = 0; i < num; i++) {
    
                    HtmlStr += `<img class="img${
      i}" src="./xingxing.png" alt="">`
                }
                this.innerHTML = HtmlStr
                flag = false
            }
            for (let i = 0; i < num; i++) {
    
                let classImg = document.getElementsByClassName(`img${
      i}`)[0]
                classImg.style.top = y - 15 + 'px'
                classImg.style.left = x - 15 + 'px'
            }
            e.preventDefault()
        })
        divBox.addEventListener('mousemove', function (e) {
    
            let x = e.clientX
            let y = e.clientY
            if (flag) {
    
                let HtmlStr = '';
                for (let i = 0; i < num; i++) {
    
                    HtmlStr += `<img class="img${
      i}" src="./xingxing.png" alt="">`
                }
                this.innerHTML = HtmlStr
                flag = false
            }
            for (let i = 0; i < num; i++) {
    
                let classImg = document.getElementsByClassName(`img${
      i}`)[0]
                classImg.style.top = y - 15 + 'px'
                classImg.style.left = x - 15 + 'px'
            }
            e.preventDefault()
        })
        btn.addEventListener('click', function () {
    
            if (!isNaN(inp.value) && inp.value != '') {
    
                if (inp.value > 10 || inp.value <= 0) {
    
                    window.alert('请输入小于十大于零')
                }
                num = inp.value
                divBox.style.display = 'block'
            } else {
    
                window.alert('请输入数字')
                return
            }
        })
    </script>
</body>

</html>

奖励一颗小星星