1
1
1
1
1
1
1
1
1
1
1
1
4
4
4
4
8
6
6
12

快乐扑克牌 www.nu0j.com The default grid system provided in Bootstrap utilizes 12 columns that render out at widths of 724px, 940px (default without responsive CSS included), and 1170px. Below 767px viewports, the columns become fluid and stack vertically.

<div class="row">
    <div class="span4">...</div>
    <div class="span8">...</div>
</div>

As shown here, a basic layout can be created with two "columns", each spanning a number of the 12 foundational columns we defined as part of our grid system.

Offsetting columns

4
4 offset 4
3 offset 3
3 offset 3
8 offset 4
<div class="row">
  <div class="span4">...</div>
  <div class="span4 offset4">...</div>
</div>

Nesting columns

With the static (non-fluid) grid system in Bootstrap, nesting is easy. To nest your content, just add a new .row and set of .span* columns within an existing .span* column.

Example

Nested rows should include a set of columns that add up to the number of columns of it's parent. For example, two nested .span3 columns should be placed within a .span6.

Level 1 of column
Level 2
Level 2
<div class="row">
  <div class="span6">
    Level 1 column
    <div class="row">
      <div class="span3">Level 2</div>
      <div class="span3">Level 2</div>
    </div>
  </div>
</div>

Fluid columns

1
1
1
1
1
1
1
1
1
1
1
1
4
4
4
4
8
6
6
12

Percents, not pixels

The fluid grid system uses percents for column widths instead of fixed pixels. It also has the same responsive variations as our fixed grid system, ensuring proper proportions for key screen resolutions and devices.

Fluid rows

Make any row fluid simply by changing .row to .row-fluid. The columns stay the exact same, making it super straightforward to flip between fixed and fluid layouts.

Markup

<div class="row-fluid">
  <div class="span4">...</div>
  <div class="span8">...</div>
</div>

Fluid nesting

Nesting with fluid grids is a bit different: the number of nested columns doesn't need to match the parent. Instead, your columns are reset at each level because each row takes up 100% of the parent column.

Fluid 12
Fluid 6
Fluid 6
<div class="row-fluid">
  <div class="span12">
    Level 1 of column
    <div class="row-fluid">
      <div class="span6">Level 2</div>
      <div class="span6">Level 2</div>
    </div>
  </div>
</div>
Variable Default value Description
@gridColumns 12 Number of columns
@gridColumnWidth 60px Width of each column
@gridGutterWidth 20px Negative space between columns

Variables in LESS

Built into Bootstrap are a handful of variables for customizing the default 940px grid system, documented above. All variables for the grid are stored in variables.less.

How to customize

Modifying the grid means changing the three @grid* variables and recompiling Bootstrap. Change the grid variables in variables.less and use one of the four ways documented to recompile. If you're adding more columns, be sure to add the CSS for those in grid.less.

Staying responsive

Customization of the grid only works at the default level, the 940px grid. To maintain the responsive aspects of Bootstrap, you'll also have to customize the grids in responsive.less.

Fixed layout

The default and simple 940px-wide, centered layout for just about any website or page provided by a single <div class="container">.

<body>
  <div class="container">
    ...
  </div>
</body>

Fluid layout

<div class="container-fluid"> gives flexible page structure, min- and max-widths, and a left-hand sidebar. It's great for apps and docs.

<div class="container-fluid">
  <div class="row-fluid">
    <div class="span2">
      <!--Sidebar content-->
    </div>
    <div class="span10">
      <!--Body content-->
    </div>
  </div>
</div>

Responsive devices

What they do

Media queries allow for custom CSS based on a number of conditions—ratios, widths, display type, etc—but usually focuses around min-width and max-width.

  • Modify the width of column in our grid
  • Stack elements instead of float wherever necessary
  • Resize headings and text to be more appropriate for devices

Use media queries responsibly and only as a start to your mobile audiences. For larger projects, do consider dedicated code bases and not layers of media queries.

Supported devices

Bootstrap supports a handful of media queries in a single file to help make your projects more appropriate on different devices and screen resolutions. Here's what's included:

Label Layout width Column width Gutter width
Smartphones 480px and below Fluid columns, no fixed widths
Smartphones to tablets 767px and below Fluid columns, no fixed widths
Portrait tablets 768px and above 42px 20px
Default 980px and up 60px 20px
Large display 1200px and up 70px 30px

Requires meta tag

To ensure devices display responsive pages properly, include the viewport meta tag.

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Using the media queries

Bootstrap doesn't automatically include these media queries, but understanding and adding them is very easy and requires minimal setup. You have a few options for including the responsive features of Bootstrap:

  1. Use the compiled responsive version, bootstrap-responsive.css
  2. Add @import "responsive.less" and recompile Bootstrap
  3. Modify and recompile responsive.less as a separate file

Why not just include it? Truth be told, not everything needs to be responsive. Instead of encouraging developers to remove this feature, we figure it best to enable it.

  /* Landscape phones and down */
  @media (max-width: 480px) { ... }

  /* Landscape phone to portrait tablet */
  @media (max-width: 767px) { ... }

  /* Portrait tablet to landscape and desktop */
  @media (min-width: 768px) and (max-width: 979px) { ... }

  /* Large desktop */
  @media (min-width: 1200px) { ... }

Responsive utility classes

What are they

For faster mobile-friendly development, use these basic utility classes for showing and hiding content by device.

When to use

Use on a limited basis and avoid creating entirely different versions of the same site. Instead, use them to complement each device's presentation.

For example, you might show a <select> element for nav on mobile layouts, but not on tablets or desktops.

Support classes

Shown here is a table of the classes we support and their effect on a given media query layout (labeled by device). They can be found in responsive.less.

Class Phones 480px and below Tablets 767px and below Desktops 768px and above
.visible-phone Visible
.visible-tablet Visible
.visible-desktop Visible
.hidden-phone Visible Visible
.hidden-tablet Visible Visible
.hidden-desktop Visible Visible

Test case

Resize your browser or load on different devices to test the above classes.

Visible on...

Green checkmarks indicate that class is visible in your current viewport.

  • Phone✔ Phone
  • Tablet✔ Tablet
  • Desktop✔ Desktop

Hidden on...

Here, green checkmarks indicate that class is hidden in your current viewport.

  • Phone✔ Phone
  • Tablet✔ Tablet
  • Desktop✔ Desktop


  • 四川黄龙自然保护区第7次发现野生大熊猫踪迹 2019-04-16
  • 施芝鸿:吹响新时代新的伟大进军的冲锋号 2019-04-08
  • 您好,这个东西没法说.上次某高校教授写了篇引起轰动.恰巧我碰到他在接头买肉夹镆,并且当时他一口气就吃三个.我毫不客气的说,您能一口气能吃三个肉夹镆就是最大的身份 2019-04-08
  • 13少年被逼参与盗窃遭烟头烫伤 21天撬130辆车 2019-04-05
  • Chongqing to open 86 civil air defense projects freely for the public to enjoy the cool - Chongqing News - CQNEWS 2019-04-05
  • 包车司机借口“学炒股”敲开门 抢钱后杀人抛尸 2019-04-03
  • 祝湖州市少年儿童节日快乐 2019-04-03
  • 五个时尚小心机,为你打造完美身形 2019-03-28
  • 梁家河,一个中国村庄的幸福与奋斗 2019-03-28
  • 践行五四精神 勇担青春使命 2019-03-26
  • 90年历史事件和历史口号 2019-03-22
  • 一个企业里的劳动力,有可能被叫做职工,意指按职责做事的人,也可能被叫做劳工,意指按劳动力做事的人。不同的称呼,体现了不同的企业性质与追求。懂这点,你才明白这“意 2019-03-20
  • 拉萨市第三高级中学举行“四讲四爱”教育实践活动之军民共建协议签订仪式 2019-03-19
  • 物智 —频道 春城壹网 七彩云南 一网天下 2019-03-15
  • 水立方年底启动“水变冰”改造 2019-03-02
  • 855| 290| 149| 978| 270| 796| 334| 796| 209| 575|