文章目录
- 一、两栏布局的实现
- 1. float+margin
- 2. flaot+BFC
- 3. 定位+margin
- 4. flex 布局
- 5. grid布局
- 二、三栏布局的实现
- 1. float + margin
- 2. float + BFC
- 3. 定位 + margin(或者定位+BFC)
- 4. flex布局
- 5. 圣杯布局
- 6. 双飞翼布局
一、两栏布局的实现
两栏布局其实就是左侧定宽,右侧自适应的布局
1. float+margin
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| .container { |
| display: flex; |
| height: 300px; |
| } |
| .left { |
| width: 100px; |
| background: red; |
| } |
| .right { |
| flex: 1; |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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2. flaot+BFC
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| .container { |
| display: flex; |
| height: 300px; |
| } |
| .left { |
| width: 100px; |
| background: red; |
| } |
| .right { |
| flex: 1; |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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知识课堂
先来看两个相关的概念:
●Box: Box是CSS布局的对象和基本单位,一个页面是由很多个Box组成的,这个Box就是我们所说的盒模型。
●Formatting context: 块级上下文格式化,它是页面中的一块渲染区域,并且有一 套渲染规则,它决定了其子元素将如何定位,以及和其他元素的关系和相互作用。
块格式化上下文(Block Formatting Context, BFC) 是Web页面的可视化CSS渲染的一部分,是布局过程中生成块级盒子的区域,也是浮动元素与其他元素的交互限定区域。
通俗来讲: BFC是一 -个独立的布局环境,可以理解为一个容器,在这个容器中按照一定规则进行物品摆放,并且不会影响其它环境中的物品。如果一个元素符合触发BFC的条件,则BFC中的元素布局不受外部影响。
创建BFC的条件:
●根元素: body;
●元素设置浮动: float除none以外的值;
●元素设置绝对定位: position (absolute、 fixed);
●display值为: inline-block、 table-cell、 table-caption、 flex等 ;
●overflow值为: hidden、 auto、 scroll;
BFC的特点:
●垂直方向上,自.上而下排列,和文档流的排列方式-致。
●在BFC中上下相邻的两个容器的margin会重叠
●计算BFC的高度时,需要计算浮动元素的高度
●BFC区域不会与浮动的容器发生重叠
●BFC是独立的容器,容器内部元素不会影响外部元素●每个元素的左margin值和容器的左border相接触
3. 定位+margin
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| * { |
| padding: 0; |
| margin: 0; |
| box-sizing: border-box; |
| } |
| .left { |
| position: absolute; |
| left: 0; |
| width: 100px; |
| height: 300px; |
| background: red; |
| } |
| .right { |
| margin-left: 100px; |
| height: 300px; |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="left"></div> |
| <div class="right"></div> |
| </body> |
| </html> |
| |
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4. flex 布局
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| .container { |
| display: flex; |
| height: 300px; |
| } |
| .left { |
| width: 100px; |
| background: red; |
| } |
| .right { |
| flex: 1; |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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5. grid布局
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| .container { |
| display: grid; |
| grid-template-columns: 100px 1fr; |
| box-sizing: border-box; |
| height: 300px; |
| } |
| .left { |
| background: red; |
| } |
| .right { |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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二、三栏布局的实现
左右定宽,中间自适应
1. float + margin
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <title>CSS实现三栏布局1</title> |
| <style type="text/css"> |
| .left { |
| width: 200px; |
| height: 300px; |
| background-color: #dc698a; |
| float: left; |
| } |
| .middle { |
| height: 300px; |
| background-color: #8cb08b; |
| margin: 0 200px; |
| } |
| .right { |
| width: 200px; |
| height: 300px; |
| background-color: #3eacdd; |
| float: right; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="left">左栏</div> |
| <div class="right">右栏</div> |
| <div class="middle">中间栏</div> |
| </body> |
| </html> |
| |
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2. float + BFC
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <title>CSS实现三栏布局1</title> |
| <style type="text/css"> |
| .left { |
| width: 200px; |
| height: 300px; |
| background-color: #dc698a; |
| float: left; |
| } |
| .middle { |
| height: 300px; |
| background-color: #8cb08b; |
| overflow: hidden; |
| } |
| .right { |
| width: 200px; |
| height: 300px; |
| background-color: #3eacdd; |
| float: right; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="left">左栏</div> |
| <div class="right">右栏</div> |
| <div class="middle">中间栏</div> |
| </body> |
| </html> |
| |
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注意:上面两种方法都必须先渲染right,否则right会被middle挤下来
3. 定位 + margin(或者定位+BFC)
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <title>CSS实现三栏布局3</title> |
| <style type="text/css"> |
| .container { |
| position: relative; |
| } |
| .left { |
| width: 200px; |
| height: 300px; |
| background-color: #dc698a; |
| position: absolute; |
| } |
| .middle { |
| height: 300px; |
| background-color: #8cb08b; |
| margin: 0 200px; |
| } |
| .right { |
| position: absolute; |
| right: 0; |
| top: 0; |
| width: 200px; |
| height: 300px; |
| background-color: #3eacdd; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left">左栏</div> |
| <div class="middle">中间栏</div> |
| <div class="right">右栏</div> |
| </div> |
| </body> |
| </html> |
| |
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4. flex布局
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /> |
| <title>Document</title> |
| <style> |
| .container { |
| height: 300px; |
| display: flex; |
| } |
| .left, |
| .right { |
| width: 100px; |
| background: red; |
| } |
| .center { |
| flex: 1; |
| background: green; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="left"></div> |
| <div class="center"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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5. 圣杯布局
| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <title>Title</title> |
| <style> |
| .container { |
| height: 200px; |
| overflow: hidden; |
| padding: 0 200px; |
| } |
| .center { |
| width: 100%; |
| height: 200px; |
| background-color: green; |
| float: left; |
| } |
| .left { |
| width: 200px; |
| height: 200px; |
| background-color: blue; |
| float: left; |
| margin-left: -100%; |
| position: relative; |
| left: -200px; |
| } |
| .right { |
| width: 200px; |
| height: 200px; |
| background-color: darkorchid; |
| float: left; |
| margin-left: -200px; |
| position: relative; |
| right: -200px; |
| } |
| </style> |
| </head> |
| <body> |
| <div class="container"> |
| <div class="center"></div> |
| <div class="left"></div> |
| <div class="right"></div> |
| </div> |
| </body> |
| </html> |
| |
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6. 双飞翼布局