Mastering CSS Animations: How to Handle Z-Index Like a Pro (With Examples)

Hey there, front-end friends! Ever had one of those moments where your CSS animation is cruising along, looking slick, and then BAM! — something weird happens, and your layout goes haywire?

Well, if you’ve dealt with z-index transitions, you know exactly what I’m talking about.

I recently found myself working on a layout for a speaker showcase. The hover animation was nice — until it wasn’t. Everything was going well, but when I hovered off one image and onto another, the previous one would mysteriously dive behind the next. Not good. The culprit? That sneaky z-index.

Why Z-Index Transitions Are a Tricky Business

Unlike properties like width, height, or scale, z-index doesn’t transition smoothly. When you hover over an element, it doesn’t gradually move up in layers like you might hope. It just jumps — kinda like a squirrel startled by a lawnmower.

Let’s say you’ve got some images stacked on top of each other with position: absolute. When you hover on one image, it should pop in front, right?

Well, the problem is that when the hover ends, the image might not return to its original position properly, causing weird glitches where images overlap unexpectedly.