CSS Margins

Inherited: No
As you may have guessed, the margin
property declares the margin between an
(X)HTML element and the elements around it.
The margin property can be set for the top,
left, right and bottom of an element. (see
example below)

margin-top: length percentage or auto;
margin-left: length percentage or auto;
margin-right: length percentage or auto;
margin-bottom: length percentage or auto;
As you can also see in the above example
you have 3 choices of values for the margin
property
length
percentage
auto
You can also declare all the margins of an
element in a single property as follows:
margin: 10px 10px 10px 10px;
If you declare all 4 values as I have above,
the order is as follows:
01. top
02. right
03. bottom
04. left
If only one value is declared, it sets the
margin on all sides. (see below)
margin: 10px;
If you only declare two or three values, the
undeclared values are taken from the
opposing side. (see below)
margin: 10px 10px; /* 2 values */
margin: 10px 10px 10px; /* 3 values */
You can set the margin property to negative
values. If you do not declare the margin value
of an element, the margin is 0 (zero).
margin: -10px;
Elements like paragraphs have default
margins in some browsers, to combat this set
the margin to 0 (zero).
p {margin: 0;}
Note: You do not have to add px (pixels) or
whatever units you use, if the value is 0
(zero).
You can see in the example below, the
elements for this site are set to be 20px
(pixels) from the body
body{
  margin: 20px;
background: #eeeeee;
font-size: small;
font-family: Tahoma, Arial, “Trebuchet MS”,
Helvetica, sans-serif;
text-align: left;
}