margin-bottom

The margin-bottom CSS property of an element sets the margin space required on the bottom of an element. A negative value is also allowed.

This property has no effect on non-replaced inline elements, like <tt> or <span>.

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.
Inherited	no
Percentages	refer to the width of the containing block
Media	visual
Computed value	the percentage as specified or the absolute length
Animation type	a length
Canonical order	the unique non-ambiguous order defined by the formal grammar

Syntax

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

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

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

Values

<length>

Specifies a fixed width. See <length> for possible values.

<percentage>

A <percentage> always relative to the width of the containing block.

auto

See margin.

Formal syntax

<length> | <percentage> | auto

Example

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;
}

Specifications

Specification	Status	Comment
CSS Basic Box Model The definition of 'margin-bottom' in that specification.	Working Draft	No significant change
CSS Transitions The definition of 'margin-bottom' in that specification.	Working Draft	Defines margin-bottom as animatable.
CSS Level 2 (Revision 1) The definition of 'margin-bottom' in that specification.	Recommendation	Removes its effect on inline elements.
CSS Level 1 The definition of 'margin-bottom' in that specification.	Recommendation	Initial definition

Browser compatibility