Html css item center

align-items

The CSS align-items property sets the align-self value on all direct children as a group. In Flexbox, it controls the alignment of items on the Cross Axis. In Grid Layout, it controls the alignment of items on the Block Axis within their grid area.

The interactive example below demonstrates some of the values for align-items using grid layout.

Try it

Syntax

/* Basic keywords */ align-items: normal; align-items: stretch; /* Positional alignment */ /* align-items does not take left and right values */ align-items: center; /* Pack items around the center */ align-items: start; /* Pack items from the start */ align-items: end; /* Pack items from the end */ align-items: flex-start; /* Pack flex items from the start */ align-items: flex-end; /* Pack flex items from the end */ align-items: self-start; /* Pack flex items from the start */ align-items: self-end; /* Pack flex items from the end */ /* Baseline alignment */ align-items: baseline; align-items: first baseline; align-items: last baseline; /* Overflow alignment (for positional alignment only) */ align-items: safe center; align-items: unsafe center; /* Global values */ align-items: inherit; align-items: initial; align-items: revert; align-items: revert-layer; align-items: unset; 

Values

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

• In absolutely-positioned layouts, the keyword behaves like start on replaced absolutely-positioned boxes, and as stretch on all other absolutely-positioned boxes.
• In static position of absolutely-positioned layouts, the keyword behaves as stretch .
• For flex items, the keyword behaves as stretch .
• For grid items, 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 .
• The property doesn’t apply to block-level boxes, and to table cells.

The cross-start margin edges of the flex items are flushed with the cross-start edge of the line.

The cross-end margin edges of the flex items are flushed with the cross-end edge of the line.

The flex items’ margin boxes are centered within the line on the cross-axis. If the cross-size of an item is larger than the flex container, it will overflow equally in both directions.

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

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

The items are packed flush to the edge of the alignment container’s start side of the item, in the appropriate axis.

The items are packed flush to the edge of the alignment container’s end side of the item, in the appropriate axis.

baseline , first baseline , last baseline

All flex items are aligned such that their flex container baselines align. The item with the largest distance between its cross-start margin edge and its baseline is flushed with the cross-start edge of the line.

Flex items are stretched such that the cross-size of the item’s margin box is the same as the line while respecting width and height constraints.

Used alongside an alignment keyword. If the chosen keyword means that the item overflows the alignment container causing data loss, the item is instead aligned as if the alignment mode were start .

Used alongside an alignment keyword. Regardless of the relative sizes of the item and alignment container and whether overflow which causes data loss might happen, the given alignment value is honored.

Formal definition

Formal syntax

align-items =
normal |
stretch |
|
[ ? ]

=
[ first | last ]? &&
baseline

=
unsafe |
safe

=
center |
start |
end |
self-start |
self-end |
flex-start |
flex-end

Examples

CSS

#container  height: 200px; width: 240px; align-items: center; /* Can be changed in the live sample */ background-color: #8c8c8c; > .flex  display: flex; flex-wrap: wrap; > .grid  display: grid; grid-template-columns: repeat(auto-fill, 50px); > div > div  box-sizing: border-box; border: 2px solid #8c8c8c; width: 50px; display: flex; align-items: center; justify-content: center; > #item1  background-color: #8cffa0; min-height: 30px; > #item2  background-color: #a0c8ff; min-height: 50px; > #item3  background-color: #ffa08c; min-height: 40px; > #item4  background-color: #ffff8c; min-height: 60px; > #item5  background-color: #ff8cff; min-height: 70px; > #item6  background-color: #8cffff; min-height: 50px; font-size: 30px; > select  font-size: 16px; > .row  margin-top: 10px; > 

HTML

div id="container" class="flex"> div id="item1">1div> div id="item2">2div> div id="item3">3div> div id="item4">4div> div id="item5">5div> div id="item6">6div> div> div class="row"> label for="display">display: label> select id="display"> option value="flex">flexoption> option value="grid">gridoption> select> div> div class="row"> label for="values">align-items: label> select id="values"> option value="normal">normaloption> option value="flex-start">flex-startoption> option value="flex-end">flex-endoption> option value="center" selected>centeroption> option value="baseline">baselineoption> option value="stretch">stretchoption> option value="start">startoption> option value="end">endoption> option value="self-start">self-startoption> option value="self-end">self-endoption> option value="first baseline">first baselineoption> option value="last baseline">last baselineoption> option value="safe center">safe centeroption> option value="unsafe center">unsafe centeroption> option value="safe right">safe rightoption> option value="unsafe right">unsafe rightoption> option value="safe end">safe endoption> option value="unsafe end">unsafe endoption> option value="safe self-end">safe self-endoption> option value="unsafe self-end">unsafe self-endoption> option value="safe flex-end">safe flex-endoption> option value="unsafe flex-end">unsafe flex-endoption> select> div> 

const values = document.getElementById("values"); const display = document.getElementById("display"); const container = document.getElementById("container"); values.addEventListener("change", (evt) =>  container.style.alignItems = evt.target.value; >); display.addEventListener("change", (evt) =>  container.className = evt.target.value; >); 

Result

Specifications

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CSS Layout — Horizontal & Vertical Align

Setting the width of the element will prevent it from stretching out to the edges of its container.

The element will then take up the specified width, and the remaining space will be split equally between the two margins:

This div element is centered.

Example

Note: Center aligning has no effect if the width property is not set (or set to 100%).

Center Align Text

To just center the text inside an element, use text-align: center;

Example

Tip: For more examples on how to align text, see the CSS Text chapter.

Center an Image

To center an image, set left and right margin to auto and make it into a block element:

Example

Left and Right Align — Using position

One method for aligning elements is to use position: absolute; :

In my younger and more vulnerable years my father gave me some advice that I’ve been turning over in my mind ever since.

Example

Note: Absolute positioned elements are removed from the normal flow, and can overlap elements.

Left and Right Align — Using float

Another method for aligning elements is to use the float property:

Example

The clearfix Hack

Note: If an element is taller than the element containing it, and it is floated, it will overflow outside of its container. You can use the «clearfix hack» to fix this (see example below).

Without Clearfix

With Clearfix

Then we can add the clearfix hack to the containing element to fix this problem:

Example

Center Vertically — Using padding

There are many ways to center an element vertically in CSS. A simple solution is to use top and bottom padding :

Example

To center both vertically and horizontally, use padding and text-align: center :

I am vertically and horizontally centered.

Example

Center Vertically — Using line-height

Another trick is to use the line-height property with a value that is equal to the height property:

I am vertically and horizontally centered.

Example

.center <
line-height: 200px;
height: 200px;
border: 3px solid green;
text-align: center;
>

/* If the text has multiple lines, add the following: */
.center p line-height: 1.5;
display: inline-block;
vertical-align: middle;
>

Center Vertically — Using position & transform

If padding and line-height are not options, another solution is to use positioning and the transform property:

I am vertically and horizontally centered.

Example

.center <
height: 200px;
position: relative;
border: 3px solid green;
>

.center p margin: 0;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
>

Tip: You will learn more about the transform property in our 2D Transforms Chapter.

Center Vertically — Using Flexbox

You can also use flexbox to center things. Just note that flexbox is not supported in IE10 and earlier versions:

Example

.center <
display: flex;
justify-content: center;
align-items: center;
height: 200px;
border: 3px solid green;
>

Tip: You will learn more about Flexbox in our CSS Flexbox Chapter.

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