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目录

CSS margin-bottom Property

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Example

Set the bottom margin for a <p> element to 25 pixels:

p.ex1 {
  margin-bottom: 25px;
}
Try it Yourself »

More "Try it Yourself" examples below.

Definition and Usage

The margin-bottom property sets the bottom margin of an element.

Note: Negative values are allowed.

Show demo ❯

Default value: 0
Inherited: no
Animatable: yes, see individual properties. Read about animatable Try it
Version: CSS1
JavaScript syntax: object.style.marginBottom="100px" Try it

Browser Support

The numbers in the table specify the first browser version that fully supports the property.

Property
margin-bottom 1.0 6.0 1.0 1.0 3.5

CSS Syntax

margin-bottom: length|auto|initial|inherit;

Property Values

Value Description Demo
length Specifies a fixed bottom margin in px, cm, em, etc. Default value is 0. Negative values are allowed. Read about length units Demo ❯
% Specifies a bottom margin in percent of the width of the containing element Demo ❯
auto The browser calculates a bottom margin Demo ❯
initial Sets this property to its default value. Read about initial
inherit Inherits this property from its parent element. Read about inherit

Margin Collapse

Top and bottom margins of elements are sometimes collapsed into a single margin that is equal to the largest of the two margins.

This does not happen on horizontal (left and right) margins! Only vertical (top and bottom) margins!

Look at the following example:

Example

p.a {
  margin: 30px 0;
}

p.b {
  margin: 20px 0;
}
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In the example above, the <p class="a"> element has a top and bottom margin of 30px. The <p class="b"> element has a top and bottom margin of 20px.

This means that the vertical margin between <p class="a"> and <p class="b"> should be 50px (30px + 20px). But due to margin collapse, the actual margin ends up being 30px!

More Examples

Example

Set the bottom margin for a <p> element to 10% of the width of the container:

p.ex1 {
  margin-bottom: 10%;
}
Try it Yourself »

Example

Set the bottom margin for a <p> element to 2 em:

p.ex1 {
  margin-bottom: 2em;
}
Try it Yourself »

Related Pages

CSS tutorial: CSS Margin

HTML DOM reference: marginBottom property


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