justify-items

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句法
形式定义
形式句法
范例
规范
浏览器兼容性
另请参阅
相关话题

CSS justify-items property defines the default justify-self for all items of the box, giving them all a default way of justifying each box along the appropriate axis.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

The effect of this property is dependent of the layout mode we are in:

In block-level layouts, it aligns the items inside their containing block on the inline axis.
For absolutely-positioned elements, it aligns the items inside their containing block on the inline axis, accounting for the offset values of top, left, bottom, and right.
In table cell layouts, this property is ignored ( more about alignment in block, absolute positioned and table layout)
In flexbox layouts, this property is ignored ( more about alignment in Flexbox)
In grid layouts, it aligns the items inside their grid areas on the inline axis ( more about alignment in grid layouts)

句法

/* Basic keywords */
justify-items: auto;
justify-items: normal;
justify-items: stretch;
/* Positional alignment */
justify-items: center;     /* Pack items around the center */
justify-items: start;      /* Pack items from the start */
justify-items: end;        /* Pack items from the end */
justify-items: flex-start; /* Equivalent to 'start'. Note that justify-items is ignored in Flexbox layouts. */
justify-items: flex-end;   /* Equivalent to 'end'. Note that justify-items is ignored in Flexbox layouts. */
justify-items: self-start;
justify-items: self-end;
justify-items: left;       /* Pack items from the left */
justify-items: right;      /* Pack items from the right */
/* Baseline alignment */
justify-items: baseline;
justify-items: first baseline;
justify-items: last baseline;
/* Overflow alignment (for positional alignment only) */
justify-items: safe center;
justify-items: unsafe center;
/* Legacy alignment */
justify-items: legacy right;
justify-items: legacy left;
justify-items: legacy center;
/* Global values */
justify-items: inherit;
justify-items: initial;
justify-items: unset;

This property can take one of four different forms:

Basic keywords: one of the keyword values normal , auto ，或 stretch .
Baseline alignment: the baseline keyword, plus optionally one of first or last .
Positional alignment: one of: center , start , end , flex-start , flex-end , self-start , self-end , left ，或 right . Plus optionally safe or unsafe .
Legacy alignment: the legacy keyword, followed by one of left or right .

值

auto

The value used is the value of the


justify-items

property of the parents box, unless the box has no parent, or is absolutely positioned, in these cases,


auto

represents


normal

normal

The effect of this keyword is dependent of the layout mode we are in:

In block-level layouts, the keyword is a synonym of start .
In absolutely-positioned layouts, the keyword behaved like start on replaced absolutely-positioned boxes, and as stretch on all other absolutely-positioned boxes.
In table cell layouts, this keyword has no meaning as this property is ignored .
In flexbox layouts, this keyword has no meaning as this property is ignored.
In grid layouts, this keyword leads to a behavior similar to the one of stretch , except for boxes with an aspect ratio or an intrinsic sizes where it behaves like start .

start

The item is packed flush to each other toward the start edge of the alignment container in the appropriate axis.

end

The item is packed flush to each other toward the end edge of the alignment container in the appropriate axis.

flex-start

For items that are not children of a flex container, this value is treated like


start

flex-end

For items that are not children of a flex container, this value is treated like

end

self-start

The item is packed flush to the edge of the alignment container of the start side of the item, in the appropriate axis.

self-end

The item is packed flush to the edge of the alignment container of the end side of the item, in the appropriate axis.

center

The items are packed flush to each other toward the center of the of the alignment container.

left

The items are packed flush to each other toward the left edge of the alignment container. If the property’s axis is not parallel with the inline axis, this value behaves like


start

right

The items are packed flush to each other toward the right edge of the alignment container in the appropriate axis. If the property’s axis is not parallel with the inline axis, this value behaves like


start

baseline first baseline last baseline

Specifies participation in first- or last-baseline alignment: aligns the alignment baseline of the box’s first or last baseline set with the corresponding baseline in the shared first or last baseline set of all the boxes in its baseline-sharing group.
The fallback alignment for


first baseline


start

, the one for


last baseline

end

stretch

If the combined size of the items is less than the size of the alignment container, any


auto

-sized items have their size increased equally (not proportionally), while still respecting the constraints imposed by


max-height


max-width

(or equivalent functionality), so that the combined size exactly fills the alignment container.

safe

If the size of the item overflows the alignment container, the item is instead aligned as if the alignment mode were


start

unsafe

Regardless of the relative sizes of the item and alignment container, the given alignment value is honored.

legacy

Makes the value inherited by the box descendants. Note that if a descendant has a


justify-self: auto

value, the


legacy

keyword is not considered by the descend, only the


left


right

，或


center

value associated to it.

形式定义

初始值	`legacy`
适用于	所有元素
继承	no
计算值	如指定
动画类型	discrete

形式句法

normal | stretch | <baseline-position> | <overflow-position>? [ <self-position> | left | right ] | legacy | legacy && [ left | right | center ]where 
<baseline-position> = [ first | last ]? baseline
<overflow-position> = unsafe | safe
<self-position> = center | start | end | self-start | self-end | flex-start | flex-end

范例

Simple demonstration

In the following example we have a simple 2 x 2 grid layout. Initially the grid container is given a justify-items value of stretch (the default), which causes the grid items to stretch across the entire width of their cells.

If you hover or tab onto the grid container however, it is given a justify-items value of center , which causes the grid items to span only as wide as their content width, and align in the center of their cells.

HTML

<article class="container" tabindex="0">
  <span>First child</span>
  <span>Second child</span>
  <span>Third child</span>
  <span>Fourth child</span>
</article>

CSS

html {
  font-family: helvetica, arial, sans-serif;
  letter-spacing: 1px;
}
article {
  background-color: red;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-auto-rows: 40px;
  grid-gap: 10px;
  width: 300px;
  justify-items: stretch;
}
article:hover, article:focus {
  justify-items: center;
}
article span {
  background-color: black;
  color: white;
  margin: 1px;
  text-align: center;
}
article, span {
  padding: 10px;
  border-radius: 7px;
}
article {
  margin: 20px;
}

结果

规范

规范	状态	注释
CSS Box Alignment Module Level 3 The definition of 'justify-items' in that specification.	工作草案	初始定义

浏览器兼容性

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Support in Flex layout

更新 GitHub 上的兼容性数据

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
Supported in Flex Layout	Chrome 完整支持 52	Edge 完整支持 12	Firefox 完整支持 20	IE 完整支持 11	Opera 完整支持 12.1	Safari 完整支持 9	WebView Android 完整支持 52	Chrome Android 完整支持 52	Firefox Android 完整支持 20	Opera Android 完整支持 12.1	Safari iOS 完整支持 9	Samsung Internet Android 完整支持 6.0

图例

完整支持

Support in Grid layout