grid隐式网格布局的学习

本次案例，新学习的grid布局方式，完全用这种方式来把各个不同的功能块罗列出来。本次只是熟悉了基本的使用方法。
隐式布局

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>grid隐士网格布局案例</title>
    <style>
        *{
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html{
            font-size: 100px;
        }
        body{
            font-size: 0.16rem;
        }
        .box{
            margin: auto;
            display: grid;
            width: 12rem;
            grid-auto-columns: repeat(12,1fr);
            grid-auto-rows: repeat(12,1fr);
            grid-auto-flow: row;
            gap:0.05rem;
        }
        .header{
            height: 1rem;
            grid-column:1/span 12;
            background-color: cornflowerblue;
        }
        .nav{
            height: 0.5rem;
            grid-column:1/span 12;
            background-color:chocolate;   
        }
        .minibox{
            height: 0.2rem;
            grid-column: 1/span 12;
        }
        .menu{
            height: 5rem;
            grid-column:1/span 3;
            grid-row:4/span 5;
            background-color: darksalmon;
        }
        .banner{
            height: 3rem;
            grid-column:4/span 6;
            grid-row:4/span 3;
            background-color: gray;
        }
        .user{
            height: 3rem;
            grid-column:10/span 3;
            grid-row: 4/span 3;
            background-color: magenta;
        }
        .ad1{
            grid-column: 4/span 9;
            grid-row: 6/span 3;
            background-color: lime;
        }
        .left{
            grid-column: 1/span 4;
            grid-row:10/span 1;
            background-color:blueviolet;
        }
        .center{
            grid-column: 5/span 4;
            grid-row:10/span 1;
            background-color:green;
        }
        .right{
            grid-column: 9/span 4;
            grid-row:10/span 1;
            background-color: goldenrod;
        }
        .footer{
            height: 2rem;
            grid-column: 1/span 12;
            background-color: black;
        }
        }
    </style>
</head>
<body>
    <div class="box">
        <div class="header">我是头部我跨越了12栏</div>
        <nav class="nav">我是导航我跨越了12栏</nav>
        <div class="minibox"> </div>
        <div class="menu">item-4</div>
        <div class="banner">item-5</div>
        <div class="user">item-6</div>
        <div class="ad1">item-7</div>
        <div class="minibox">item-8</div>
        <div class="left">item-9</div>
        <div class="center">item-10</div>
        <div class="right">item-11</div>
        <div class="footer">item-12</div>
        <div class="item">item-13</div>
    </div>
</body>
</html>