Here are some notes about ordering layers. I’ve seen a bunch of projects the last few weeks that try to use the ‘z’ to order the layers but trip over a difference in Chrome and Safari how this is handled.
In short, using the ‘z’ works in Safari, but not in Chrome, but you should not use it to order layers. The ‘z’ value is not the z-index, but the z-coordinate in 3D space. If you want to order the layers, you should use the ‘index’ property or the ordering functions (like ‘placeBehind’).
Here’s a small project to showing the differences: