Tagged “positioning”

David cleverly uses CSS alone (and only a few lines) to show a “back to top” link only after the user has started scrolling, then pin its position to the bottom-left of the screen.

There’s a great section on Source order and layers in Every Layout’s Imposter layout. It’s a reminder that when needing to layer one element on top of the other you should:

1. favour a modern layout approach such as CSS Grid over absolute positioning; and
2. not apply z-index unless it’s necessary.

which elements appear over which is, by default, a question of source order. That is: if two elements share the same space, the one that appears above the other will be the one that comes last in the source.

z-index is only necessary where you want to layer positioned elements irrespective of their source order. It’s another kind of override, and should be avoided wherever possible.

An arms race of escalating z-index values is often cited as one of those irritating but necessary things you have to deal with using CSS. I rarely have z-index problems, because I rarely use positioning, and I’m mindful of source order when I do.

A while back I bookmarked Michelle Barker’s CSS Grid based overlay technique which neatly allows layering one element atop another using CSS Grid rather than absolute positioning. Now, Stephanie Eckles has taken the idea a step further with her Smol Stack Layout which offers a more flexible markup structure, some intuitive grid area naming and a neat aspect-ratio API.

Need to overlay one HTML element on top of and fully covering another, such as a heading with translucent background on top of an image? Michelle Barker has us covered with this blog post in which she creates an overlay utility to handle this. She firstly shows how it can be accomplished with positioning, then modernises her code using the inset CSS logical property, before finally demonstrating a neat CSS Grid based approach.