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

河南十一选五走势图' www.f4dx.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


  • 山东将推动各类保护区范围内煤矿有序退出 2019-04-21
  • 四川宝兴硗碛藏乡牧民与牦牛上演“别样舞会” 2019-04-21
  • 你遇到了吗用户吐槽升iOS 11.4后耗电过快用户吐槽升iOS11后耗电过快-行情资讯 2019-04-09
  • 山西--山西频道--人民网 2019-04-09
  • 贵州省委常委赵德明任贵阳市委书记(图简历) 2019-04-08
  • 甜点大危机!吃糖导致皮肤老化,了解一下? 2019-04-05
  • 张洪忠:人工智能是一种技术迭代,不是对人的替代 2019-04-05
  • “霉斑”还是“曜变天目”? 2019-04-03
  • 一条塔里木河 串起南疆各色景致与无限风光 2019-04-01
  • 《剩女时代》解析性别歧视等现象背后的“剩女”成因性别歧视剩女 2019-04-01
  • 红色大悟公开征集城市形象系列作品 2019-03-30
  • 在楼主大谈共产主义分配的时候,希望楼主先说明一下对马克思关于共产主义基本原则的理解。一个社会如果仍然存在“按劳动分配”,怎么会是“每一个个人的全面而自由的发展” 2019-03-21
  • 世界杯俄罗斯大胜沙特 网友:戈洛温一战成名 2019-03-14
  • 紫光阁中共中央国家机关工作委员会 2019-03-08
  • 明星待遇!俄罗斯神猫预测2018世界杯揭幕战胜者 2019-02-28
  • 877| 925| 72| 267| 660| 376| 171| 806| 539| 597| 464| 840| 631| 689| 566|