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Use .container-fluid for a full width container, spanning the entire width of your viewport.

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Bootstrap includes a responsive, mobile first fluid grid system that appropriately scales up to 12 columns as the device or viewport size increases. It includes predefined classes for easy layout options, as well as powerful mixins for generating more semantic layouts.

Introduction

Grid systems are used for creating page layouts through a series of rows and columns that house your content. Here's how the Bootstrap grid system works:

• Rows must be placed within a .container [fixed-width] or .container-fluid [full-width] for proper alignment and padding.
• Use rows to create horizontal groups of columns.
• Content should be placed within columns, and only columns may be immediate children of rows.
• Predefined grid classes like .row and .col-xs-4 are available for quickly making grid layouts. Less mixins can also be used for more semantic layouts.
• Columns create gutters [gaps between column content] via padding. That padding is offset in rows for the first and last column via negative margin on .rows.
• The negative margin is why the examples below are outdented. It's so that content within grid columns is lined up with non-grid content.
• Grid columns are created by specifying the number of twelve available columns you wish to span. For example, three equal columns would use three .col-xs-4.
• If more than 12 columns are placed within a single row, each group of extra columns will, as one unit, wrap onto a new line.
• Grid classes apply to devices with screen widths greater than or equal to the breakpoint sizes, and override grid classes targeted at smaller devices. Therefore, e.g. applying any .col-md-* class to an element will not only affect its styling on medium devices but also on large devices if a .col-lg-* class is not present.

Look to the examples for applying these principles to your code.

We use the following media queries in our Less files to create the key breakpoints in our grid system.

/* Extra small devices [phones, less than 768px] */
/* No media query since this is the default in Bootstrap */

/* Small devices [tablets, 768px and up] */
@media [min-width: @screen-sm-min] { ... }

/* Medium devices [desktops, 992px and up] */
@media [min-width: @screen-md-min] { ... }

/* Large devices [large desktops, 1200px and up] */
@media [min-width: @screen-lg-min] { ... }

We occasionally expand on these media queries to include a max-width to limit CSS to a narrower set of devices.

@media [max-width: @screen-xs-max] { ... }
@media [min-width: @screen-sm-min] and [max-width: @screen-sm-max] { ... }
@media [min-width: @screen-md-min] and [max-width: @screen-md-max] { ... }
@media [min-width: @screen-lg-min] { ... }

Grid options

See how aspects of the Bootstrap grid system work across multiple devices with a handy table.