CSS Layout - CSS position CSS

The position property specifies the type of positioning method used for an element (static, relative, fixed, absolute or sticky).

The position Property

The position property specifies the type of positioning method used for an element.

There are five different position values:

• static
• relative
• fixed
• absolute
• sticky

Elements are then positioned using the top, bottom, left, and right properties. However, these properties will not work unless the position property is set first. They also work differently depending on the position value.

position: static;

HTML elements are positioned static by default.

Static positioned elements are not affected by the top, bottom, left, and right properties.

An element with position: static; is not positioned in any special way; it is always positioned according to the normal flow of the page:

An element with position: relative; is positioned relative to its normal position.

Setting the top, right, bottom, and left properties of a relatively-positioned element will cause it to be adjusted away from its normal position. Other content will not be adjusted to fit into any gap left by the element.

An element with position: fixed; is positioned relative to the viewport, which means it always stays in the same place even if the page is scrolled. The top, right, bottom, and left properties are used to position the element.

A fixed element does not leave a gap in the page where it would normally have been located.

Notice the fixed element in the lower-right corner of the page. Here is the CSS that is used:

An element with position: absolute; is positioned relative to the nearest positioned ancestor (instead of positioned relative to the viewport, like fixed).

However; if an absolute positioned element has no positioned ancestors, it uses the document body, and moves along with page scrolling.

Note: A "positioned" element is one whose position is anything except static.

An element with position: sticky; is positioned based on the user's scroll position.

A sticky element toggles between relative and fixed, depending on the scroll position. It is positioned relative until a given offset position is met in the viewport - then it "sticks" in place (like position:fixed).

Note: Internet Explorer, Edge 15 and earlier versions do not support sticky positioning. Safari requires a -webkit- prefix (see example below). You must also specify at least one of top, right, bottom or left for sticky positioning to work.

In this example, the sticky element sticks to the top of the page (top: 0), when you reach its scroll position.

The overflow property specifies whether to clip the content or to add scrollbars when the content of an element is too big to fit in the specified area.

The overflow property has the following values:

• visible - Default. The overflow is not clipped. The content renders outside the element's box
• hidden - The overflow is clipped, and the rest of the content will be invisible
• scroll - The overflow is clipped, and a scrollbar is added to see the rest of the content
• auto - Similar to scroll, but it adds scrollbars only when necessary

Note: The overflow property only works for block elements with a specified height.

Note: In OS X Lion (on Mac), scrollbars are hidden by default and only shown when being used (even though "overflow:scroll" is set).

overflow: visible

By default, the overflow is visible, meaning that it is not clipped and it renders outside the element's box:

With the hidden value, the overflow is clipped, and the rest of the content is hidden:

Setting the value to scroll, the overflow is clipped and a scrollbar is added to scroll inside the box. Note that this will add a scrollbar both horizontally and vertically (even if you do not need it):

The auto value is similar to scroll, but it adds scrollbars only when necessary:

The overflow-x and overflow-y properties specifies whether to change the overflow of content just horizontally or vertically (or both):

overflow-x specifies what to do with the left/right edges of the content.
overflow-y specifies what to do with the top/bottom edges of the content.

The float Property

The float property is used for positioning and formatting content e.g. let an image float left to the text in a container.

The float property can have one of the following values:

• left - The element floats to the left of its container
• right - The element floats to the right of its container
• none - The element does not float (will be displayed just where it occurs in the text). This is default
• inherit - The element inherits the float value of its parent

In its simplest use, the float property can be used to wrap text around images.

Example - float: right;

The following example specifies that an image should float to the right in a text:

The following example specifies that an image should float to the left in a text:

In the following example the image will be displayed just where it occurs in the text (float: none;):

The clear property specifies what elements can float beside the cleared element and on which side.

The clear property can have one of the following values:

• none - Allows floating elements on both sides. This is default
• left - No floating elements allowed on the left side
• right- No floating elements allowed on the right side
• both - No floating elements allowed on either the left or the right side
• inherit - The element inherits the clear value of its parent

The most common way to use the clear property is after you have used a float property on an element.

When clearing floats, you should match the clear to the float: If an element is floated to the left, then you should clear to the left. Your floated element will continue to float, but the cleared element will appear below it on the web page.

The following example clears the float to the left. Means that no floating elements are allowed on the left side (of the div):

If an element is taller than the element containing it, and it is floated, it will "overflow" outside of its container:

Then we can add overflow: auto; to the containing element to fix this problem:

With the float property, it is easy to float boxes of content side by side:

Use float with a list of hyperlinks to create a horizontal menu: