夜间模式的开启与关闭，父模板的制作

夜间模式的开启与关闭
1. 放置点击的按钮或图片。
2. 定义开关切换函数。
3. onclick函数调用。

父模板的制作

制作网站网页共有元素的父模板html，包括顶部导航，中间区块划分，底部导航，底部说明等。
汇总相关的样式形成独立的css文件。
汇总相关的js代码形成独立的js文件。
形成完整的base.html+css+js

导航html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>base</title>
    <link rel="stylesheet" href="../static/css/base.css" type="text/css">
    <script src="../static/JS/base.js"></script>

</head>
<body id="myBody">
<nav>

    <div class="layui-col-md4">
        <div class="layui-row" style="padding-top:10px;">
            <img id="myOnOff" onclick="myswitch()" src="http://www.runoob.com/images/pic_bulbon.gif" width="40px"
                 style="padding-left: 10px;">
            <a href="http://localhost:63342/denglu1.1/templates/shouye.html?_ijt=qijfc55i74avkg8umf7nn7oqt7">首页</a>
            <a href="http://localhost:63342/denglu1.1/templates/denglu1.1.html?_ijt=7qkhljvviqhhrvp78f6nv1jtqn">Login</a>
            <a href="http://localhost:63342/denglu1.1/templates/%E6%B3%A8%E5%86%8C.html?_ijt=bpr6ikepnp2sh7actb82n1m3dt">Enroll</a>

        </div>
    </div>
    <br>
    <form method="get" action="#">
        <div class="layui-row">
            <div class="layui-col-md3" style="padding-left: 50px;">
                <input type="text" name="title" required lay-verify="required"
                       placeholder="search"
                       autocomplete="off" class="layui-input">
            </div>
            <div class="layui-col-md3" style="padding-left: 50px;">
                <button type="submit" class="layui-btn layui-btn-primary">搜索</button>
            </div>
        </div>
    </form>
    </div></nav>
<div class="area">

</div>


<div class="area1">
    <div class="img">
        <a href="https://baike.so.com/doc/5456803-24643565.html"><img
                src="http://img5.iqilu.com/c/u/2017/0222/1487776284427.jpg"></a>
        <div class="desc"><a
                href="https://baike.so.com/doc/1750829-1851093.html?from=120785&sid=1851093&redirect=search">panda</a>
        </div>
    </div>
    <div class="img">
        <a href="https://baike.so.com/doc/2269087-2400571.html"><img
                src="http://pic1.win4000.com/wallpaper/9/533e618008c98.jpg"></a>
        <div class="desc"><a href="https://www.duitang.com/blog/?id=156020766">熊猫壁纸</a></div>
    </div>

</div>

<br>
<br>
<footer>
    <div class="footer_box">
        Copyright@ 2017-2022 个人版权，版权所有　　陈楠芸　　
    </div>
</footer>
</body>
</html>

导航css

.img {
    border: 1px solid #cccccc;
    width: 250px;
    margin: 5px;
    float: left;

}

div.img img {
    width: 100%;
    height: auto;
}

div.desc {
    text-align: center;
    padding: 5px;
}

div.img:hover {
    border: 1px solid #000000;
}

.area {
    height: 300px;
}


.area1 {
    height: 300px;
}

.area2 {
    height: 300px;


 nav{
    position:fixed;
    top:0px;
    height: 58px;
    background-color:#FCFCFC;
    border-bottom:1px solid #DDDDDD;
    width:100%;
 }

 footer.footer_box{
    background-color: #002D54;
    padding: 10px;
    color : #FFFFFF;
    text-align: center;
 }

导航js

   function myswitch() {
            var oBody = document.getElementById("myBody");
            var oOnoff = document.getElementById("myOnOff");
            if(oOnoff.src.match("bulbon")){
                oOnoff.src="http://www.runoob.com/images/pic_bulboff.gif";
                oBody.style.background="black";
                oBody.style.color ="white";
            }else{
                oOnoff.src="http://www.runoob.com/images/pic_bulbon.gif";
                 oBody.style.background="white";
                oBody.style.color ="black";
            }
        }

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>夜间模式</title>
    <script>
        function myswitch() {
            var oBody = document.getElementById("myBody");
            var oOnoff = document.getElementById("myOnOff");
            if(oOnoff.src.match("bulbon")){
                oOnoff.src="http://www.runoob.com/images/pic_bulboff.gif";
                oBody.style.background="black";
                oBody.style.color ="white";
            }else{
                oOnoff.src="http://www.runoob.com/images/pic_bulbon.gif";
                 oBody.style.background="white";
                oBody.style.color ="black";
            }
        }
    </script>
</head>
<body id="myBody">
<img id="myOnOff" onclick="myswitch()" src="http://www.runoob.com/images/pic_bulbon.gif" width="40px">
<script>document.write(Date())</script>
</body>
</ht