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margin-bottom

The margin-bottom CSS property sets the margin area on the bottom of an element. A positive value places it farther from its neighbors, while a negative value places it closer.

Try it

The effect of the CSS margin-bottom property on the element box

This property has no effect on non-replaced inline elements, such as <span> or <code>.

Syntax

/* <length> values */
margin-bottom: 10px; /* An absolute length */
margin-bottom: 1em; /* relative to the text size */
margin-bottom: 5%; /* relative to the nearest block container's width */

/* Keyword values */
margin-bottom: auto;

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

The margin-bottom property is specified as the keyword auto, or a <length>, or a <percentage>. Its value can be positive, zero, or negative.

Values

<length>: The size of the margin as a fixed value.
<percentage>: The size of the margin as a percentage, relative to the inline size (width in a horizontal language, defined by writing-mode) of the containing block.
auto: The browser selects a suitable value to use. See margin.

Formal definition

Initial value	`0`
Applies to	all elements, except elements with table `display` types other than `table-caption`, `table` and `inline-table`. It also applies to `::first-letter` and `::first-line`.
Inherited	no
Percentages	refer to the width of the containing block
Computed value	the percentage as specified or the absolute length
Animation type	a length

Formal syntax

margin-bottom = 
  <length-percentage>  |
  auto                 

<length-percentage> = 
  <length>      |
  <percentage>

Examples

Setting positive and negative bottom margins

HTML

<div class="container">
  <div class="box0">Box 0</div>
  <div class="box1">Box 1</div>
  <div class="box2">Box one's negative margin pulls me up</div>
</div>

CSS

CSS for divs to set margin-bottom and height

.box0 {
  margin-bottom: 1em;
  height: 3em;
}
.box1 {
  margin-bottom: -1.5em;
  height: 4em;
}
.box2 {
  border: 1px dashed black;
  border-width: 1px 0;
  margin-bottom: 2em;
}

Some definitions for container and divs so margins' effects can be seen more clearly

.container {
  background-color: orange;
  width: 320px;
  border: 1px solid black;
}
div {
  width: 320px;
  background-color: gold;
}

Result

Specifications

Specification
CSS Box Model Module Level 3 # margin-physical

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`margin-bottom`	1	12	1	3	3.5	1	4.4	18	4	10.1	1	1.0
`auto`	1	12 The `auto` value is not supported in quirks mode.	1	6 The `auto` value is not supported in quirks mode.	3.5	1	37	18	4	14	1	1.0