OCT. 2016 UPDATE
-moz-element() property doesn't seem to be widely supported by other browsers except to FF, there's an even easier technique to apply blurring without affecting the contents of the container. The use of pseudoelements is ideal in this case in combination with svg blur filter.
Check the demo using pseudo-element
(Demo was tested in FF v49, Chrome v53, Opera 40 - IE doesn't seem to support blur either with css or svg filter)
The only way (so far) of having a blur effect in the background without js plugins, is the use of
-moz-element() property in combination with the
svg blur filter. With
-moz-element() you can define an element as a background image of another element. Then you apply the
svg blur filter. OPTIONAL: You can utilize some jQuery for scrolling if your background is in
I understand it is a quite complicated solution and limited to FF (
element() applies only to Mozilla at the moment with
-moz-element() property) but at least there's been some effort in the past to implement in webkit browsers and hopefully it will be implemented in the future.
~ Answered on 2013-05-13 13:18:42