javas实现下拉菜单

样式有些丑陋，各位看官看看就好

下面是代码部分

 HTML

<ul class="nav">
        <li>
            <h4>水果</h4>
            <ul  class="item">
                <li>香蕉</li>
                <li>苹果</li>
                <li>葡萄</li>
            </ul>
        </li>
        <li>
            <h4>水果</h4>
            <ul class="item">
                <li>香蕉</li>
                <li>苹果</li>
                <li>葡萄</li>
            </ul>
        </li>
        <li>
            <h4>水果</h4>
            <ul class="item">
                <li>香蕉</li>
                <li>苹果</li>
                <li>葡萄</li>
            </ul>
        </li>
        <li>
            <h4>水果</h4>
            <ul class="item">
                <li>香蕉</li>
                <li>苹果</li>
                <li>葡萄</li>
            </ul>
        </li>
        <li>
            <h4>水果</h4>
            <ul class="item">
                <li>香蕉</li>
                <li>苹果</li>
                <li>葡萄</li>
            </ul>
        </li>
    </ul>

css

    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .nav{
            width: 500px;
            margin: 100px auto;
        }
        .nav li{
            list-style: none;
            float: left;
            width: 80px;
            height: 45px;
            text-align: center;
            line-height: 45px;
            /* border: 1px red solid; */
        }
        .item{
            display: none;
        }
        .item li{
            border:1px pink solid;
            border-top: 0;
        }
        .nav li:hover{
            color: darkred;
            background-color: #ccc;
        }
    </style>

js

<script>
        var navs = document.querySelector('.nav')
        var lis = navs.children
        for (var i = 0; i < lis.length; i++){
            lis[i].onmouseover = function(){
                this.children[1].style.display = 'block'
            }
            lis[i].onmouseout = function(){
                this.children[1].style.display = 'none'
            }
        }
    </script>