Entendiendo el funcionamiento de “z-index” en CSS
Posted on Diciembre 18, 2007, under General.
Interesante artículo, con su página de demostración, que explica qué es y como funciona la propiedad "z-index" en el CSS. Según el artículo, estas son las reglas de oro aplicables a esta propiedad:
- A box is at the same stack level as its parent’s unless it is given a different stack level through the ‘z-index’ property.
- z-index applies only to objects that have the position property set to relative, fixed or absolute.
- Assigning an opacity value less than 1 to a positioned element implicitly creates a stacking context, just like adding a z-index value.
For a positioned box, the z-index property specifies:
- The stack level of the box in the current stacking context.
- Whether the box establishes a local stacking context.
If there is no z-index specified, elements are stacked in the following order (from back to front):
- boxes in the normal flow, according to the sequence in the source code
- floating boxes
- positioned boxes, according to the sequence in the source code
Artículo completo: http://tjkdesign.com/
Demo: Understanding z-index
