First of all, z-index only works on positioned elements. If you try to set a z-index on an element with no position specified, it will do nothing. Secondly, z-index values can create stacking contexts, and now suddenly what seemed simple just got a lot more complicated. Stacking Contexts

17 May 2016 Does the margin on the stickily positioned element affect its distance from the flow root For a positioned box, the z-index property specifies:. #outer { margin: 5em; border: 1px solid #f00; height: 4em; } #inner { width: 6em; If you specify the z-index as a positive integer, you assign it a stack level “in  Z-index, Position the element above or below other elements. If they have the same z-index, the position will depend on the order in the layout. Margin, Keep the  28 май 2019 z-index: 0; width: 100%; height: 600px; } &__text { position: relative; text-align: center; z-index: 100; margin: 3rem 0; padding: 1.5rem; } 17 Jun 2009 Since we've applied the negative margin, we can now physically see the default stacking order in action. The “article” element overlaps the “  26 Sep 2008 html, body { margin: 0; padding: 0; } #outer { margin: 5em; border: 1px solid Un z-index de 0 (zero) significa lo mismo que auto , pero hay una 

margin: margen exterior, que separa la caja del elemento de las demás. si Ten en cuenta que z-index sólo funciona con posicionamiento distinto al estático.

margin: margen exterior, que separa la caja del elemento de las demás. si Ten en cuenta que z-index sólo funciona con posicionamiento distinto al estático. The placement of a positioned box in the z-axis. The z-index example page demonstrates how the stacking order of positioned boxes can be reversed. Possible  Use padding--lv0 or margin--lv0 to completely remove any margin or padding from the element. The ! prefix is a way zin-0, z-index: inherit;. zin-lv1, z-index: 1; . Margins. The margins are used to modify the space between two elements. You can to be on front. The element with the higher Z-index will be displayed first.