2011年(34)
分类: 系统运维
2011-08-18 14:14:12
The term "CSS positioning" refers to using CSS to position elements on your HTML page. CSS allows you to position any element precisely where you want it. You can specify whether you want the element positioned relative to its natural position in the page or absolute based on its parent element.
Absolute positioning can be very useful for creating advanced layouts and cool visual effects such as overlapping elements to present a layered effect.
Relative PositioningTo perform relative positioning in CSS you use position:relative; followed by the desired offset from either top, right, bottom or left
This example offsets the element 80 pixels from the left of where it would have been. If we had specified top, it would appear 80 pixels below where it would have been. It's important to note that other elements are not affected by this element's offset. Therefore, overlapping may occur.
Absolute PositioningTo perform absolute positioning in CSS you use position:absolute; followed by the desired offset.
Fixed positioning allows you to fix the position of an element to a particular spot on the page - regardless of scrolling.