bottom
======

The **`bottom`** CSS property participates in setting the vertical position of a positioned element. It has no effect on non-positioned elements.

Try it
------

The effect of `bottom` depends on how the element is positioned (i.e., the value of the `position` property):

* When `position` is set to `absolute` or `fixed`, the `bottom` property specifies the distance between the outer edge of the element's bottom margin and the outer edge of the containing block's bottom padding.
* When `position` is set to `relative`, the `bottom` property specifies the distance the element's bottom edge is moved above its normal position.
* When `position` is set to `sticky`, the `bottom` property is used to compute the sticky-constraint rectangle.
* When `position` is set to `static`, the `bottom` property has *no effect*.

When both `top` and `bottom` are specified, `position` is set to `absolute` or `fixed`, *and* `height` is unspecified (either `auto` or `100%`) both the `top` and `bottom` distances are respected. In all other situations, if `height` is constrained in any way or `position` is set to `relative`, the `top` property takes precedence and the `bottom` property is ignored.

Syntax
------


```css
/\* <length> values \*/
bottom: 3px;
bottom: 2.4em;

/\* <percentage>s of the height of the containing block \*/
bottom: 10%;

/\* Keyword value \*/
bottom: auto;

/\* Global values \*/
bottom: inherit;
bottom: initial;
bottom: revert;
bottom: revert-layer;
bottom: unset;
```

### Values

`<length>`

A negative, null, or positive `<length>` that represents:

* for *absolutely positioned elements*, the distance to the bottom edge of the containing block.
* for *relatively positioned elements*, the distance that the element is moved above its normal position.

`<percentage>`

A `<percentage>` of the containing block's height.

`auto`

Specifies that:

* for *absolutely positioned elements*, the position of the element is based on the `top` property, while `height: auto` is treated as a height based on the content; or if `top` is also `auto`, the element is positioned where it should vertically be positioned if it were a static element.
* for *relatively positioned elements*, the distance of the element from its normal position is based on the `top` property; or if `top` is also `auto`, the element is not moved vertically at all.

`inherit`

Specifies that the value is the same as the computed value from its parent element (which might not be its containing block). This computed value is then handled as if it were a `<length>`, `<percentage>`, or the `auto` keyword.

Formal definition
-----------------

|  |  |
| --- | --- |
| Initial value | `auto` |
| Applies to | positioned elements |
| Inherited | no |
| Percentages | refer to the height of the containing block |
| Computed value | if specified as a length, the corresponding absolute length; if specified as a percentage, the specified value; otherwise, `auto` |
| Animation type | a length, percentage or calc(); |

Formal syntax
-------------
```

bottom =   
  auto                 |  
  <length-percentage>    
  
<length-percentage> =   
  <length>      |  
  <percentage>    
  
```

Examples
--------

### Absolute and fixed positioning

This example demonstrates the difference in behavior of the `bottom` property, when `position` is `absolute` versus `fixed`.

#### HTML


```html
<p>
  This<br />is<br />some<br />tall,<br />tall,<br />tall,<br />tall,<br />tall<br />content.
</p>
<div class="fixed"><p>Fixed</p></div>
<div class="absolute"><p>Absolute</p></div>
```


#### CSS


```css
p {
  font-size: 30px;
  line-height: 2em;
}

div {
  width: 48%;
  text-align: center;
  background: rgb(55 55 55 / 20%);
  border: 1px solid blue;
}

.absolute {
  position: absolute;
  bottom: 0;
  left: 0;
}

.fixed {
  position: fixed;
  bottom: 0;
  right: 0;
}
```


#### Result

Specifications
--------------

| Specification |
| --- |
| CSS Positioned Layout Module Level 3 # insets |

Browser compatibility
---------------------

BCD tables only load in the browser with JavaScript enabled. Enable JavaScript to view data.

See also
--------

* `inset`, the shorthand for all related properties: `top`, `bottom`, `left`, and `right`
* The mapped logical properties: `inset-block-start`, `inset-block-end`, `inset-inline-start`, and `inset-inline-end` and the shorthands `inset-block` and `inset-inline`
* `position`