栅格系统
使用我们强大的移动优先弹性框网格来构建各种形状和大小的布局,这得益于十二列系统、五个默认响应层、Sass 变量和混合以及数十个预定义类。
实现原理
定义:栅格系统是通过将页面划分为多个列(或称网格)来实现布局和内容分布的工具。
实现方式:通常通过 CSS 定义的固定宽度列或百分比列来构建,页面上的内容块可以放置在这些列中。
工作原理
基础单位:栅格系统基于12列或24列等网格的划分,每一列都占据页面的某一部分宽度。
排列:列之间可以有固定的间距(gutter),通过排列和组合这些列来形成不同的布局。
流式布局:栅格系统允许响应式布局,使得页面可以适应不同设备的屏幕宽度。
网格选项
虽然 Bootstrap 使用ems 或rems 来定义大多数尺寸,用于网格断点和容器宽度。这是因为视口宽度以像素为单位,不会随着字体大小而变化。
通过方便的表格了解 Bootstrap 网格系统的各个方面如何在多种设备上工作。

使用方法
基本用法
容器:栅格系统中的元素通常放在一个容器(container)内,用于约束最大宽度。
行和列:
等宽示例
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>Container</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css"> <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">等宽列</h3> <div class="row"> <div class="col border py-3 bg-light">二分之一</div> <div class="col border py-3 bg-light">二分之一</div> </div> <div class="row"> <div class="col border py-3 bg-light">三分之一</div> <div class="col border py-3 bg-light">三分之一</div> <div class="col border py-3 bg-light">三分之一</div> </div> <div class="row"> <div class="col border py-3 bg-light">四分之一</div> <div class="col border py-3 bg-light">四分之一</div> <div class="col border py-3 bg-light">四分之一</div> <div class="col border py-3 bg-light">四分之一</div>
</div> <div class="row"> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div> <div class="col border py-3 bg-light">十二分之一</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
|

设置一个列宽
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>Container</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css"> <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">设置一个列宽</h3> <div class="row"> <div class="col border py-3 bg-light">左</div> <div class="col-7 border py-3 bg-light">中</div> <div class="col border py-3 bg-light">右</div> </div> <div class="row"> <div class="col-3 border py-3 bg-light">左</div> <div class="col border py-3 bg-light">中</div> <div class="col border py-3 bg-light">右</div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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可变宽度的内容
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>Container</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css"> <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">可变宽度的内容</h3> <div class="row justify-content-md-center"> <div class="col col-lg-2 border py-3 bg-light">左</div> <div class="col-md-auto border py-3 bg-light">中(在屏幕>=768px时,可根据内容自动调整列宽度)</div> <div class="col col-lg-2 border py-3 bg-light">右</div> </div> <div class="row"> <div class="col border py-3 bg-light">左</div> <div class="col-md-auto border py-3 bg-light">中(在屏幕>=768px时,可根据内容自动调整列宽度)</div> <div class="col col-lg-2 border py-3 bg-light">右</div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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覆盖所有设备
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>Container</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">覆盖所有设备</h3> <div class="row"> <div class="col border py-3 bg-light">col</div> <div class="col border py-3 bg-light">col</div> <div class="col border py-3 bg-light">col</div> </div> <div class="row"> <div class="col-8 border py-3 bg-light">col-8</div> <div class="col-4 border py-3 bg-light">col-4</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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水平排列
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>Container</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">水平排列</h3>
<div class="row"> <div class="col-sm-8 border py-3 bg-light">col-sm-8</div> <div class="col-sm-4 border py-3 bg-light">col-sm-4</div> </div>
<div class="row"> <div class="col-md-8 border py-3 bg-light">col-md-8</div> <div class="col-md-4 border py-3 bg-light">col-md-4</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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混合搭配
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>快速掌握Bootstrap4布局</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">混合搭配</h3>
<div class="row"> <div class="col-12 col-md-8 border py-3 bg-light">.col-12 .col-md-8</div> <div class="col-6 col-md-4 border py-3 bg-light">.col-6 .col-md-4</div> </div>
<div class="row"> <div class="col-6 border py-3 bg-light">.col-6</div> <div class="col-6 border py-3 bg-light">.col-6</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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列偏移
偏移定义:使用 offset 类来使某一列向右移动一定的列数,例如 col-md-offset-3 表示该列右移3列。
用途:常用于居中对齐或创造非对称布局。
偏移类示例
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>快速掌握Bootstrap4布局</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">偏移类示例</h3> <div class="row"> <div class="col-md-6 offset-md-3 border py-3 bg-light">.col-md-6 .offset-md-3</div> </div> <div class="row"> <div class="col-md-4 offset-md-1 border py-3 bg-light">.col-md-4 .offset-md-1</div> <div class="col-md-4 offset-md-2 border py-3 bg-light">.col-md-4 .offset-md-2</div> </div> <div class="row"> <div class="col-md-4 border py-3 bg-light">.col-md-4</div> <div class="col-md-4 offset-md-4 border py-3 bg-light">.col-md-4 .offset-md-4</div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
|

使用margin类实现列偏移
使用margin类也可以完成列偏移
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>快速掌握Bootstrap4布局</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">使用margin类实现列偏移</h3> <div class="row"> <div class="col-md-4 border py-3 bg-light">.col-md-4</div> <div class="col-md-4 ml-auto border py-3 bg-light">.col-md-4 .ml-auto</div> </div> <div class="row"> <div class="col-md-3 ml-md-auto border py-3 bg-light">.col-md-3 ml-md-auto</div> <div class="col-md-3 ml-md-auto border py-3 bg-light">.col-md-3 ml-md-auto</div> <div class="col-md-3 ml-md-auto border py-3 bg-light">.col-md-3 ml-md-auto</div> </div> <div class="row"> <div class="col-auto mr-auto border py-3 bg-light">.col-auto .mr-auto</div> <div class="col-auto border py-3 bg-light">.col-auto</div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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列排序
排序类:通过 order 类来改变列的显示顺序,允许不同尺寸设备下列的重新排列。
自定义顺序:在移动端和桌面端可以使用不同的 order 值来实现灵活的布局。
排列顺序
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>快速掌握Bootstrap4布局</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css">
</head> <body class="container"> <h3 class="mb-4">排列顺序</h3>
<div class="row no-gutters"> <div class="col order-12 border py-3 bg-light">order-12</div> <div class="col order-1 border py-3 bg-light">order-1</div> <div class="col order-6 border py-3 bg-light">order-6</div> <div class="col border py-3 bg-light">col</div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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列嵌套
嵌套结构:在某一列内部再创建一行和多列,以实现更复杂的布局。
嵌套效果:通过嵌套,允许在同一列中具有不同的栅格分布,使布局更灵活。
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>快速掌握Bootstrap4布局</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css"> <style> img{ width: 100px; height: 100px; } </style> </head> <body class="container"> <h3 class="mb-4">嵌套</h3> <div class="row"> <div class="col-12 col-lg-6">
<div class="row border no-gutters"> <div class="col-12 col-sm-3"><img src="https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1592380068202&di=0eee2ce7449491428f479285020a7040&imgtype=0&src=http%3A%2F%2Fwww.cflac.org.cn%2Fxw%2F201810%2FW020181008346545600505.jpg" alt=""></div> <div class="col-12 col-sm-9 pl-3">李白诗歌的语言,有的清新如同口语,有的豪放,不拘声律,近于散文,但都统一在"清水出芙蓉,天然去雕饰"的自然美之中。</div>
</div> </div> <div class="col-12 col-lg-6">
<div class="row border no-gutters"> <div class="col-12 col-sm-3"><img src="https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1592380151056&di=17af252bd8370ee0591ecf708741f42c&imgtype=0&src=http%3A%2F%2Fimage3.cnpp.cn%2Fupload%2Fimages%2F20151227%2F00041237439_400x508.jpg" alt=""></div> <div class="col-12 col-sm-9 pl-3">在杜甫中年因其诗风沉郁顿挫,忧国忧民,杜甫的诗被称为"诗史"。他的诗词以古体,律诗见长,风格多样,以"沉郁顿挫"四字准确概括出他自己的作品风格,而以沉郁为主。</div>
</div> </div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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案例:开发电商网站特效
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| <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no"> <title>开发电商网站特效</title> <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/css/bootstrap.min.css"> <style> .product-grid{ text-align: center; overflow: hidden; position: relative; transition: all 0.5s ease 0s; } .product-grid .product-image{ overflow: hidden; } .product-grid .product-image img{ width: 100%; height: auto; transition: all 0.5s ease 0s; } .product-grid:hover .product-image img{ transform: scale(1.5); } .product-grid .product-content{ padding: 12px 12px 15px 12px; transition: all 0.5s ease 0s; } .product-grid:hover .product-content{ opacity: 0; } .product-grid .title{ font-size: 20px; font-weight: 600; margin: 0 0 10px; } .product-grid .title a{ color: #000; } .product-grid .title a:hover{ color: #2e86de; } .product-grid .price{ font-size: 18px; font-weight: 600; color: #2e86de; } .product-grid .price span{ color: #999; font-size: 15px; font-weight: 400; text-decoration: line-through; margin-left: 7px; display: inline-block; } .product-grid .social{ background-color: #fff; width: 100%; padding: 0; margin: 0; list-style: none; opacity: 0; position: absolute; bottom: -50%; transition: all 0.5s ease 0s; } .product-grid:hover .social{ opacity: 1; bottom: 20px; } .product-grid .social li{ display: inline-block; } .product-grid .social li a{ color: #909090; font-size: 16px; line-height: 45px; text-align: center; height: 45px; width: 45px; margin: 0 7px; border: 1px solid #909090; border-radius: 50px; display: block; position: relative; transition: all 0.5s ease-in-out;
} .product-grid .social li a:hover{ color: #fff; background-color: #2e86de; } </style> </head> <body class="container"> <div class="row"> <div class="col-md-3 col-sm-6"> <div class="product-grid">
<div class="product-image"> <a href="#"> <img class="pic-1" src="./images/touxiang.jpg" alt=""> </a>
</div>
<div class="product-content"> <h3 class="title"><a href="#">男士衬衫</a></h3> <div class="price">¥29.00 <span>$14.00</span> </div> </div>
<ul class="social"> <li><a href=""><i class="fa fa-search"></i></a></li> <li><a href=""><i class="fa fa-shopping-bag"></i></a></li> <li><a href=""><i class="fa fa-shopping-cart"></i></a></li> </ul> </div> </div> <div class="col-md-3 col-sm-6"> <div class="product-grid">
<div class="product-image"> <a href="#"> <img class="pic-1" src="./images/touxiang.jpg" alt=""> </a>
</div>
<div class="product-content"> <h3 class="title"><a href="#">男士衬衫</a></h3> <div class="price">¥29.00 <span>$14.00</span> </div> </div>
<ul class="social"> <li><a href=""><i class="fa fa-search"></i></a></li> <li><a href=""><i class="fa fa-shopping-bag"></i></a></li> <li><a href=""><i class="fa fa-shopping-cart"></i></a></li> </ul> </div> </div> <div class="col-md-3 col-sm-6"> <div class="product-grid">
<div class="product-image"> <a href="#"> <img class="pic-1" src="./images/touxiang.jpg" alt=""> </a>
</div>
<div class="product-content"> <h3 class="title"><a href="#">男士衬衫</a></h3> <div class="price">¥29.00 <span>$14.00</span> </div> </div>
<ul class="social"> <li><a href=""><i class="fa fa-search"></i></a></li> <li><a href=""><i class="fa fa-shopping-bag"></i></a></li> <li><a href=""><i class="fa fa-shopping-cart"></i></a></li> </ul> </div> </div> <div class="col-md-3 col-sm-6"> <div class="product-grid">
<div class="product-image"> <a href="#"> <img class="pic-1" src="./images/touxiang.jpg" alt=""> </a>
</div>
<div class="product-content"> <h3 class="title"><a href="#">男士衬衫</a></h3> <div class="price">¥29.00 <span>$14.00</span> </div> </div>
<ul class="social"> <li><a href=""><i class="fa fa-search"></i></a></li> <li><a href=""><i class="fa fa-shopping-bag"></i></a></li> <li><a href=""><i class="fa fa-shopping-cart"></i></a></li> </ul> </div> </div> </div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.4.1/js/bootstrap.min.js"></script> </body> </html>
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1.整体布局结构:
- 使用了一个包含整个页面的 container-fluid 容器,以便页面可以全宽度适应不同屏幕。
- 通过 row 类创建了每个大块(如头部、导航、内容、页脚)的行。
- 在每一行中,使用 col 类定义不同列的宽度和排列方式。
2.头部(Header):
- 头部占据整行(col-12),显示了招商银行的标题和一句标语。
- 样式上设置了背景色、文字颜色,并进行了内边距和文本居中的处理。
3.导航(Navigation):
- 导航栏使用了6个等宽的列,每个列代表一个导航项。
- 使用响应式类 col-12 col-md-2,在小屏幕上每个导航项占据整行,而在中等及以上屏幕上每个导航项只占两列。
4.横幅(Banner):
- 横幅区域使用了一整行(col-12),在这里显示欢迎信息和简单的说明,背景色和内边距使内容更突出。
5.主要内容区域(Main Content):
- 主体内容分为两部分:左边的主要内容(col-12 col-md-8)和右边的次要内容(col-12 col-md-4)。
- 在左边的列中,嵌套了两行(row),每行包含一个“最新动态”和“在线服务”的功能块(feature)。
- 右边的列只包含一个“客户支持”功能块。
6.页脚(Footer):
- 页脚占据一整行(col-12),用于展示版权信息,背景色为深色以与页面其他部分形成对比。
移动优先设计:通过 col-12 类,所有内容在移动设备上均为整行显示,然后利用 col-md-* 类在中等及以上屏幕上调整布局。
灵活排列:不同列的宽度和顺序根据设备的宽度进行调整,以确保最佳用户体验。