css div纵向排列

CSS Div纵向排列基础概念

CSS（层叠样式表）是一种用于描述HTML文档样式的语言。在CSS中，可以使用多种方法来实现div元素的纵向排列。

类型及应用场景

1. 普通流布局（Normal Flow）

默认情况下，元素按照文档顺序从上到下、从左到右排列。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Vertical Alignment</title>
    <style>
        .container {
            width: 200px;
        }
        .box {
            width: 100px;
            height: 50px;
            margin-bottom: 10px;
        }
        .box1 { background-color: red; }
        .box2 { background-color: green; }
        .box3 { background-color: blue; }
    </style>
</head>
<body>
    <div class="container">
        <div class="box box1"></div>
        <div class="box box2"></div>
        <div class="box box3"></div>
    </div>
</body>
</html>

2. 绝对定位（Absolute Positioning）

通过设置position: absolute;和top、bottom属性，可以实现元素的绝对定位。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Vertical Alignment</title>
    <style>
        .container {
            position: relative;
            width: 200px;
        }
        .box {
            width: 100px;
            height: 50px;
        }
        .box1 { background-color: red; position: absolute; top: 0; }
        .box2 { background-color: green; position: absolute; top: 60px; }
        .box3 { background-color: blue; position: absolute; top: 120px; }
    </style>
</head>
<body>
    <div class="container">
        <div class="box box1"></div>
        <div class="box box2"></div>
        <div class="box box3"></div>
    </div>
</body>
</html>

3. Flexbox布局（Flexbox Layout）

Flexbox是一种一维布局模型，适用于各种复杂的布局需求。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Vertical Alignment</title>
    <style>
        .container {
            display: flex;
            flex-direction: column;
            width: 200px;
        }
        .box {
            width: 100px;
            height: 50px;
        }
        .box1 { background-color: red; }
        .box2 { background-color: green; }
        .box3 { background-color: blue; }
    </style>
</head>
<body>
    <div class="container">
        <div class="box box1"></div>
        <div class="box box2"></div>
        <div class="box box3"></div>
    </div>
</body>
</html>

4. 网格布局（Grid Layout）

CSS Grid布局是一种二维布局模型，适用于更复杂的布局需求。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Vertical Alignment</title>
    <style>
        .container {
            display: grid;
            grid-template-rows: repeat(3, 50px);
            width: 200px;
        }
        .box {
            width: 100px;
        }
        .box1 { background-color: red; }
        .box2 { background-color: green; }
        .box3 { background-color: blue; }
    </style>
</head>
<body>
    <div class="container">
        <div class="box box1"></div>
        <div class="box box2"></div>
        <div class="box box3"></div>
    </div>
</body>
</html>