Positioning

2:31:00 PM |

Fixed Positioning

An element with fixed position is positioned relative to the browser window.
It will not move even if the window is scrolled:

Example

p.pos_fixed
{
position:fixed;
top:30px;
right:5px;
}
Note: IE7 and IE8 support the fixed value only if a !DOCTYPE is specified.
Fixed positioned elements are removed from the normal flow. The document and other elements behave like the fixed positioned element does not exist.
Fixed positioned elements can overlap other elements.

Relative Positioning

A relative positioned element is positioned relative to its normal position.

Example

h2.pos_left
{
position:relative;
left:-20px;
}
h2.pos_right
{
position:relative;
left:20px;
}

The content of relatively positioned elements can be moved and overlap other elements, but the reserved space for the element is still preserved in the normal flow.

Example

h2.pos_top
{
position:relative;
top:-50px;
}
Relatively positioned elements are often used as container blocks for absolutely positioned elements.

Absolute Positioning

An absolute position element is positioned relative to the first parent element that has a position other than static. If no such element is found, the containing block is <html>:

Example

h2
{
position:absolute;
left:100px;
top:150px;
}
Absolutely positioned elements are removed from the normal flow. The document and other elements behave like the absolutely positioned element does not exist.
Absolutely positioned elements can overlap other elements.

Overlapping Elements

When elements are positioned outside the normal flow, they can overlap other elements.
The z-index property specifies the stack order of an element (which element should be placed in front of, or behind, the others).
An element can have a positive or negative stack order:

Example

img
{
position:absolute;
left:0px;
top:0px;
z-index:-1
}



CSS Positioning Properties

The number in the "CSS" column indicates in which CSS version the property is defined (CSS1 or CSS2).
PropertyDescriptionValuesCSS
bottomSets the bottom margin edge for a positioned boxauto
length
%inherit		2
clipClips an absolutely positioned elementshapeauto
inherit		2
cursorSpecifies the type of cursor to be displayedurlauto
crosshair
default
pointer
move
e-resize
ne-resize
nw-resize
n-resize
se-resize
sw-resize
s-resize
w-resize
text
wait
help		2
leftSets the left margin edge for a positioned boxauto
length
%inherit		2
overflowSpecifies what happens if content overflows an element's boxauto
hidden
scroll
visible
inherit		2
positionSpecifies the type of positioning for an elementabsolute
fixed
relative
static
inherit		2
rightSets the right margin edge for a positioned boxauto
length
%inherit		2
topSets the top margin edge for a positioned boxauto
length
%inherit		2
z-indexSets the stack order of an elementnumberauto
inherit		2